Three ring Circus - RRT-0, SR3, U2 control ring impressions

Blindasabat

Flashlight Enthusiast
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I lined up the three control ring lights I have to compare and give my impressions of how well they work. The three subjects are the JetBeam RRT-0 Raptor, Nitecore SR3, and SureFire U2A.

Ring feel:
The three vary in several ways in how the ring moves. The RRT-0's metal ring turns easily with little friction and strong detents, though there is a tiny little wiggle room in the detents - though this is not bothersome. The SR3 has more friction in the ring than the RRT. It turns smoothly and has softer detents. It still works well, and I like the feel of it. The SureFire U2 has no detents and the highest friction by far among the three. It is all smooth sliding friction holding the ring in place. There is no tactile feel for level switching, but if its on, that is no problem. I think I like the SR3 ring the best here, but it is close among all three.

Range of motion:
The RRT-0 turns about 120 degrees for four detents. Easy to operate the entire range with one hand motion. SR3 has about 300 degrees of travel. It requires about three two finger twists to go from lowest to highest with one hand hold. With two hands, you still need to do one big extreme twist to go full range. You need to pretwist your hands to do it, so it takes a try or two the first time to get it right. The detents are useful for pre-setting the level you want, though out of 8 levels I will never remember other than high and low, so the detents are of less value in the middle range. The U2 has just about 120 degrees of motion for six levels. It is still hard to twist the full range since the friction is somewhat high. My earlier LuxV U2 had a little less friction and I could operate that one more easily one handed, but this one is a little tighter and the ring is not as aggressively grippy as the SR3, so it is harder to turn one handed without a firm squeeze. I like the range of motion and number of levels of the U2 best. I just wish it was as easy to turn as my silky smooth first one

Levels:
The RRT-0 has four levels at any one time, with low switchable to a low-low via a quick twist from low (lvl 1) to lvl 2 & back. Regular low is so close to level 2 that I don't know why they didn't make the low-low permanent and make high-high the option. There is a big gap from level 3 (50L) to level 4 (220L, really around 175 OTF to my eyes). It is not a big problem, but it would be nice to have a level between 100-125L for some good performance at better run time. The SR3 is better here with a wide range of levels, probably more than needed since I have yet to use all of them. I would prefer a lower low on all of them. I think the U2 is best here. The levels are evenly spaced visually, there are enough, but not too many.

Mechanics of the ring:
The U2 and SR3 use magnet(s) and sensors, I assume the RRT-0 does too. Only the SR3 can be taken apart so the ring is separate from the driver and LED (easily - by me). The RRT ring is smallest and most compact, but can not be taken apart to look at. Neither can the U2 - at least not by me (see posts below how to, though). The SR3 driver assembly can be easily removed from the ring assembly and re-assemled backwards to swap the positions of the upper and lower four levels. Put it together wrong and you will get levels in this order as you turn the ring: 5, 6, 7, 8, 1, 2, 3, 4. There is no way to tell which way is correct unless you remember the alignment of the printing on the body of the light when you take it apart. Both RRT-0 and SR3 rings are metal while the U2 ring is plastic on the outside with magnet completely hidden.

Quality of operation:
The RRT-0 and SR3 both have issues in normal use. The RRT-0 has a delay turning on that appears to be in the driver, not the switch. It then sometimes flashes briefly at max even when on low. This most often happens when manually strobing but sometimes when I just press it quickly. Not really a ring issue as it does not do it when changing levels. The SR3 has better switch action, though it turns on in low, then immediately goes to the selected level. This is very quick and hard to see, but ti sometimes appears as hesitation like the RRT-0. It does not change levels as smoothly all the time. It sometimes flashes enough while changing modes into or out of max to make it switch into strobe mode, which I hate. I have taken to turning it off before dialing it to max sometimes. The U2 switch works very well and predictably. The levels change abruptly and immediately with dial movement once it has moved far enough which almost catches you by surprise due to the lack of detents to indicate a new level. It operates without any hiccups or unexpected flashes, mode changes, or surprises. The mode change locations are spot-on consistent even without detents. It is almost fluid feeling. It overall shows a higher level of development that takes more time and money but feels awesome to use.

This is really a control ring comparison, but I'll comment on some other factors too.

Beams & Output:
My RRT-0 came with a smooth reflector, so it is very ringy with the XR-E R2. It is very bright with throw about equal to the SR3 with it's bigger reflector, but the hotspot, though small, still seemed to have a slight donut hole I could only see on white walls, but since I don't hunt those, It typically never bothered me. The SR3 beam is smoother with only slight artifacts and rings due to its MOP reflector. But the U2 beam laid them all to waste with an SSC P4.
Output of the RRT-0 an SR3 seem slightly less than advertised - must be emitter lumens. The U2 only claims 100 or 120L, but was almost as bright and has much more runtime (4 hrs), but of course uses twice the battery and is much larger. You can choose your level on all of these based on runtime required anyway, so that is not a huge issue. The U2 will just last longer before needing a battery change.

Ergonomics:
The RRT-0 is OK for the typical overhand carry to turn on-off, but the cigar hold is not to my liking due to the tailcap rim being the only thing to hold onto. It is too close to the tail to be comfortable to hold. The SR3 is bulky for a single cell light, but has enough geometric features to supply good grip anywhere. The placement of the tactical cross grip over 25mm from the tail switch, and it's cross shape makes for good cigar grip. The U2 is good for overhand and underhand carry - feeling great either way. It has a subtle ring around the top of the clip that is in a good place for cigar hold and would be enough if the light was not as long and heavy headed. it's good, but not great. Overall, the U2 is best for it's purpose as a bigger all-around light. The RRT-0 is good for a small light that will more likely be in my pocket - and often is lately.

Value;
I strongly considered the RRT-0 at full price, but ended up getting a used one for slightly less and consider it worth it. The SR3 was not worth list to me so I got it on clearance sale for a good price (before the RRT-0). The U2 (to me) was not worth the almost $300 full list price, but I pieced my 18650 body and U2A SSC head together out of two separate CPF MarketPlace purchases. Cost me about half of retail. Very worth it.

Summary:
We have three different lights with three different control rings that work in similar ways, but are not the same. The size, styling, clips (or lack of), beams, output, and ergonomics are all different. Two have steel bezel rings which help keep from getting dinged so easily - which I like as I have dinged a few bezels in my day. This makes each good for different things, and I like each of them for different uses, but overall I like the RRT-0 the best since I like EDC size lights and this has decent output. It was easy to take apart to drop in a Q3 5A (thanks DaFabricata!), fits HDS bezel rings (see picture (but not all versions since there are many people making or who have made these), has a deep carry pocket clip (very important to me for ease of carry) and I was able to drop in an optic that improved the beam a little for me and softened the spill cut-off that I find distracting moving around in trees, rough terrain, and foliage. The U2 is second because of the excellent ring, 18650 support (mine at least) smooth beam, great overall ergonomics, consistent response of the clicky and ring, solid feel, excellent clip that works even on thin jacket pockets, long runtime even on high, and dashing good looks. I don't carry it because I wear dress pants most of the time, but I did coat pocket carry it daily for the first month or two since it was so nice to use. I can't wait for neutral XP-G's to come out so I can send it out for an upgrade (only because few people can open it) to improve the tint and roughly double it's output to around 300L. It is the best as an all-around the house, farm, car camping, and utilitarian light. The Nitecore SR3 is no slouch and a very cool light, it is just caught in the middle of this trio. Too big for my pants pockets, and seems like it carries a small battery for it's size. It gets some coat pocket carry and is good at what it does. Has plenty of modes with a nice slide-n-click ring to access them. It is easy to open to access the LED too. The big steel bezel was tight, but came off by hand with a rubber pad jar opener. It wasn't glued. The rest of it is even easier to access. It needs a tint upgrade, but I have not yet decided how warm to go.

<edit>: some T1A impressions added in post #11. I only handled it once, so take my impressions for what they are worth.
Some
 
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EXCELLENT post! A very useful comparison indeed, answering a lot of questions about ring-selector lights.

I'm not sure if you wanted it to be considered for the Review section, but it is a very valuable contribution which many members will appreciate, and I think it deserves to go there.
 
I lined up the three control ring lights I have to compare and give my impressions of how well they work. The three subjects are the JetBeam RRT-0 Raptor, Nitecore SR3, and SureFire U2A.

Ring feel:
The three vary in several ways in how the ring moves. The RRT-0's metal ring turns easily with little friction and strong detents, though there is a tiny little wiggle room in the detents - though this is not bothersome. The SR3 has more friction in the ring than the RRT. It turns smoothly and has softer detents. It still works well, and I like the feel of it. The SureFire U2 has no detents and the highest friction by far among the three. It is all smooth sliding friction holding the ring in place. There is no tactile feel for level switching, but if its on, that is no problem. I think I like the SR3 ring the best here, but it is close among all three.

Range of motion:
The RRT-0 turns about 120 degrees for four detents. Easy to operate the entire range with one hand motion. SR3 has about 300 degrees of travel. It requires about three two finger twists to go from lowest to highest with one hand hold. With two hands, you still need to do one big extreme twist to go full range. You need to pretwist your hands to do it, so it takes a try or two the first time to get it right. The detents are useful for pre-setting the level you want, though out of 8 levels I will never remember other than high and low, so the detents are of less value in the middle range. The U2 has just about 90 degrees of motion for six levels. It is still hard to twist the full range since the friction is somewhat high. My earlier LuxV U2 had a little less friction and I could operate that one more easily one handed, but this one is a little tighter and the ring is not as aggressively grippy as the SR3, so it is harder to turn one handed without a firm squeeze. I like the range of motion and number of levels of the U2 best. I just wish it was as easy to turn as my silky smooth first one

Levels:
The RRT-0 has four levels at any one time, with low switchable to a low-low via a quick twist from low (lvl 1) to lvl 2 & back. Regular low is so close to level 2 that I don't know why they didn't make the low-low permanent and make high-high the option. There is a big gap from level 3 (50L) to level 4 (220L, really around 175 OTF to my eyes). It is not a big problem, but it would be nice to have a level between 100-125L for some good performance at better run time. The SR3 is better here with a wide range of levels, probably more than needed since I have yet to use all of them. I would prefer a lower low on all of them. I think the U2 is best here. The levels are evenly spaced visually, there are enough, but not too many.

Mechanics of the ring:
The U2 and SR3 use magnets and sensors, I'm not sure if the RRT-0 does. Only the SR3 can be taken apart so the ring is separate from the driver and LED. The RRT ring is smallest and most compact, but can not be taken apart to look at. Neither can the U2 - at least not by me. The SR3 driver assembly can be easily removed from the ring assembly and re-assemled backwards to swap the positions of the upper and lower four levels. Put it together wrong and you will get levels in this order as you turn the ring: 5, 6, 7, 8, 1, 2, 3, 4. There is no way to tell which way is correct unless you remember the alignment of the printing on the body of the light when you take it apart. Both RRT-0 and SR3 rings are metal while the U2 ring is plastic on the outside with magnets completely hidden.

Quality of operation:
The RRT-0 and SR3 both have issues in normal use. The RRT-0 has a delay turning on that appears to be in the driver, not the switch. It then sometimes flashes briefly at max even when on low. This most often happens when manually strobing but sometimes when I just press it quickly. Not really a ring issue as it does not do it when changing levels. The SR3 has better switch action, though it turns on in low, then immediately goes to the selected level. This is very quick and hard to see, but ti sometimes appears as hesitation like the RRT-0. It does not change levels as smoothly all the time. It sometimes flashes enough while changing modes into or out of max to make it switch into strobe mode, which I hate. I have taken to turning it off before dialing it to max sometimes. The U2 switch works very well and predictably. The levels change abruptly and immediately with dial movement once it has moved far enough which almost catches you by surprise due to the lack of detents to indicate a new level. It operates without any hiccups or unexpected flashes, mode changes, or surprises. The mode change locations are spot-on consistent even without detents. It is almost fluid feeling. It overall shows a higher level of development that takes more time and money but feels awesome to use.

This is really a control ring comparison, but I'll comment on some other factors too.

Beams & Output:
My RRT-0 came with a smooth reflector, so it is very ringy with the XR-E R2. It is very bright with throw about equal to the SR3 with it's bigger reflector, but the hotspot, though small, still seemed to have a slight donut hole I could only see on white walls, but since I don't hunt those, It typically never bothered me. The SR3 beam is smoother with only slight artifacts and rings due to its MOP reflector. But the U2 beam laid them all to waste with an SSC P4.
Output of the RRT-0 an SR3 seem slightly less than advertised - must be emitter lumens. The U2 only claims 100 or 120L, but was almost as bright and has much more runtime (4 hrs), but of course uses twice the battery and is much larger. You can choose your level on all of these based on runtime required anyway, so that is not a huge issue. The U2 will just last longer before needing a battery change.

Ergonomics:
The RRT-0 is OK for the typical overhand carry to turn on-off, but the cigar hold is not to my liking due to the tailcap rim being the only thing to hold onto. It is too close to the tail to be comfortable to hold. The SR3 is bulky for a single cell light, but has enough geometric features to supply good grip anywhere. The placement of the tactical cross grip over 25mm from the tail switch, and it's cross shape makes for good cigar grip. The U2 is good for overhand and underhand carry - feeling great either way. It has a subtle ring around the top of the clip that is in a good place for cigar hold and would be enough if the light was not as long and heavy headed. it's good, but not great. Overall, the U2 is best for it's purpose as a bigger all-around light. The RRT-0 is good for a small light that will more likely be in my pocket - and often is lately.

Value;
I strongly considered the RRT-0 at full price, but ended up getting a used one for slightly less and consider it worth it. The SR3 was not worth list to me so I got it on clearance sale for a good price (before the RRT-0). The U2 (to me) was not worth the almost $300 full list price, but I pieced my 18650 body and U2A SSC head together out of two separate CPF MarketPlace purchases. Cost me about half of retail. Very worth it.

Summary:
We have three different lights with three different control rings that work in similar ways, but are not the same. The size, styling, clips (or lack of), beams, output, and ergonomics are all different. Two have steel bezel rings which help keep from getting dinged so easily - which I like as I have dinged a few bezels in my day. This makes each good for different things, and I like each of them for different uses, but overall I like the RRT-0 the best since I like EDC size lights and this has decent output. It was easy to take apart to drop in a Q3 5A (thanks DaFabricata!), fits HDS bezel rings (see picture (but not all versions since there are many people making or who have made these), has a deep carry pocket clip (very important to me for ease of carry) and I was able to drop in an optic that improved the beam a little for me and softened the spill cut-off that I find distracting moving around in trees, rough terrain, and foliage. The U2 is second because of the excellent ring, 18650 support (mine at least) smooth beam, great overall ergonomics, consistent response of the clicky and ring, solid feel, excellent clip that works even on thin jacket pockets, long runtime even on high, and dashing good looks. I don't carry it because I wear dress pants most of the time, but I did coat pocket carry it daily for the first month or two since it was so nice to use. I can't wait for neutral XP-G's to come out so I can send it out for an upgrade (only because few people can open it) to improve the tint and roughly double it's output to around 300L. It is the best as an all-around the house, farm, car camping, and utilitarian light. The Nitecore SR3 is no slouch and a very cool light, it is just caught in the middle of this trio. Too big for my pants pockets, and seems like it carries a small battery for it's size. It gets some coat pocket carry and is good at what it does. Has plenty of modes with a nice slide-n-click ring to access them. It is easy to open to access the LED too. The big steel bezel was tight, but came off by hand with a rubber pad jar opener. It wasn't glued. The rest of it is even easier to access. It needs a tint upgrade, but I have not yet decided how warm to go.

Thank you very much for your very informative comparison. I've been thinking about getting either an RRT-0 or U2 for some time since I'm quite intrigued by the selector ring user interface.

Thanks again,
Robert
 
Thanks for a great comparison.

I have a U2A and an SR3, and love them both.

I think the SR3 has gotten a bad wrap, because people place it in the wrong category. It's not a pocket light.

I bought one because I like single-cell lights best. This light has a beam and output that compares to my Olight M20 and Fenix TK10, but it's smaller.

Also, nice job piecing together a U2A on the cheap!
 
great review =)

But i think its a little unfair to compare U2's brightness with the RRT-0 and SR3 since U2 has twice the battery capacity.
 
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The SR3 and RRT-0 both claim higher brightness than the U2, so it is fair to evaluate those claims.
But I think its a little unfair to compare U2's brightness with the RRT-0 and SR3 since U2 has twice the battery capacity.
 
Excellent review, Blindasabat!

Just FYI, a good holseter for the SR3 is the Ripoffs CO - 193.

I do not know of a good holster for the RRT-0, although I am hoping the Ripoffs CO - 192 will work well, because I already own one and I use if for the Nitecore Extreme.
 
thanks for the review. Never really fond of 2 cells lights but ur post made me feel incomplete without U2 in my collection lol

btw, not for me but im sure others would appreciate if you can expand the review to include SureFire Titan or T1A 🙂
 
Range of motion:
The U2 has just about 90 degrees of motion for six levels.

For my U2A (SSC P4 emitter), the ring rotates through 135 degrees between Min and Max. It clearly is more than 90 degrees, just by marking the ring and observing its before vs after position.

Mechanics of the ring:
The U2 and SR3 use magnets and sensors, I'm not sure if the RRT-0 does. Only the SR3 can be taken apart so the ring is separate from the driver and LED. The RRT ring is smallest and most compact, but can not be taken apart to look at. Neither can the U2 - at least not by me. The SR3 driver assembly can be easily removed from the ring assembly and re-assemled backwards to swap the positions of the upper and lower four levels. Put it together wrong and you will get levels in this order as you turn the ring: 5, 6, 7, 8, 1, 2, 3, 4. There is no way to tell which way is correct unless you remember the alignment of the printing on the body of the light when you take it apart. Both RRT-0 and SR3 rings are metal while the U2 ring is plastic on the outside with magnets completely hidden.

My U2A uses one magnet (no plural) and five mag sensors.

The selector ring can be removed in at least two ways: 1) crank on the ring until in jumps the machined-in aluminum stop on the head, or 2) shim the c-clip that holds the ring in place. I found method #1 easier to accomplish.

Summary:
The U2 is second because of the excellent ring, 18650 support (mine at least) smooth beam, great overall ergonomics, consistent response of the clicky and ring, solid feel, excellent clip that works even on thin jacket pockets, long runtime even on high, and dashing good looks.

My U2A does not accept 18650 cells. It does fit 17670s.
 
I saw your U2 post. Excellent info. Helps me decide what to do to mine.

I will re-check my U2A, but when I checked it out, it seemed like 90 degrees. I didn't mark it though.
Does it matter which way you rotate the ring to remove it? What do you mean by "shim the C-clip?"
For my U2A (SSC P4 emitter), the ring rotates through 135 degrees between Min and Max.



My U2A does not accept 18650 cells. It does fit 17670s.
Yeah, My U2 body is bored out. :twothumbs
 
thanks for the review. Never really fond of 2 cells lights but ur post made me feel incomplete without U2 in my collection lol
Thanks, it is a nice light.

btw, not for me but im sure others would appreciate if you can expand the review to include SureFire Titan or T1A 🙂
Thanks!
I have played with DaFabricata's excellently modded T1A...

The bezel rotation on this size light is great for ergonomics. Easy to handle for a small light - just what I was wishing for from the RRT-0. It has soft detents (don't recall where - I think one at off and one at mid?), and a smooth turning feel. It came on extremely low such that you could stare at the emitter all day. The quality of operation was excellent with good response and good amount of friction. It doesn't have a clicky so it is all twist, but that makes a non-tactical "hand down at your side" hold normal and natural. It feels more casual that way.
The beam was nice on DeFab's, but he had modded it from what he and other describe as a very floody beam with a seemingly out of focus emitter. I don't know if SF did that on purpose for a small (their smallest) EDC style beam. The reflector is small & shallow and provides a wide spill beam and smooth spot. It seemed to have around 100L if not more - that is a guess, and that was after DeFabricata's emitter mod. If I had one, I'd send it to him to transform it from a good light to a better one. Tint and beam are important to me.
 
I saw your U2 post. Excellent info. Helps me decide what to do to mine.

I will re-check my U2A, but when I checked it out, it seemed like 90 degrees. I didn't mark it though.
Does it matter which way you rotate the ring to remove it? What do you mean by "shim the C-clip?"Yeah, My U2 body is bored out. :twothumbs

Yeah, rub it in.🙁 I wish my U2 could accept an 18650.

Re: shimming the c-clip

Here is the c-clip:
SFU2c-clip.jpg


The clip goes into the groove immediately to the left of the threads for the U2 head (you can also see the machined-in aluminum stop block next to the second o-ring on the left):
SFU2headselectorringstop.jpg


The springy c-clip sticks out slightly from the surface of the head. That protrusion is enough to catch a matching groove in the plastic selector ring (the groove is the very narrow line just below the top edge of the ring; also note the single magnet):
SFU2selectorringc-clipgroove.jpg


So the challenge is to somehow jam some stiff, thin pieces of metal in-between the c-clip and the inside face of the selector ring to free the clip from the groove in the ring. Then you can just pull the ring right off the end of the head. The fit is extremely tight and I couldn't do it. I found the twist-off method to work reliably, but it produces some gouging of the inside face of the selector ring when ring rides over the aluminum stop block (see the crease in the photo below that runs right to left from the short vertical wall to the magnet). The gouging doesn't seem to affect the stop block's function and the selector ring reliably and securely rotates only between its designed points. But I don't know if you'd want to remove the ring multiple times and risk excessive damage (I figure one might want to remove the ring periodically to lube the o-ring if and when the selector ring rotation gets overly stiff). What I did was dispense with the c-clip. The friction from the o-ring seems to be enough to hold the ring securely. However, you can accidentally (and fairly easily) pull off the ring. So now when I turn the ring, I always apply some upward force which keeps the selector ring on the head.

SFU2selectorringgougedfromthestop.jpg
 
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