JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and more!

selfbuilt

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JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and more!

Warning: This double review is more pic heavy than usual. :sweat:

The Backup lights are a new series from JetBeam, designed with the classic two-stage head twist interface. I will be reviewing the BC10 (1xCR123A) and BA20 (2xAA) models here.

For the sake of brevity, I will use mainly representative body pics from the BC10. More specific pics (including beamshots) will be included with the individual light runtime graphs and summary tables further down this review.

BC003.jpg


Common Manufacturer Specifications:
  • LED: Cree R5 LED with an output of 270 lumen.
  • Glass: Hardened Glass Lens with Anti Reflective Coating
  • Reflector: Machined Aluminum Reflector
  • Finish: HAIII Hard Anodized Mil-Spec Finish
  • Waterproof: IPX-8 Standards (2 Meters)
  • Accessories: Pocket Clip
BC10 Specs:
  • Modes: 2 Modes: High (270 Lumen), Low (30 Lumen)
  • Run Time: High - 75 minutes, Low - 18 Hours
  • Battery Type: One CR123 3V
  • Size: 23mm x 90mm
  • Weight: 47g (without battery)
  • MSRP ~$39
BA20 Specs:
  • Modes: 2 Modes: High (270 Lumen), Low (30 Lumen)
  • Run Time: High - 105 minutes, Low - 35 Hours
  • Battery Type: Two AA Batteries
  • Size: 23mm x 155mm
  • Weight: 71g (without battery)
  • MSRP ~$40
BC004.jpg

BC002.jpg


Packaging is fairly typical for these sorts of lights (i.e. simple cardboard box with molded plastic insert). Inside you will find the light, manual, warranty card, wrist lanyard, spare o-rings and spare switch boot cover.

All dimensions given with no batteries installed:

BC10: Weight: 46.6g, Length: 90.3mm, Width (bezel) 23.2mm
BA20: Weight: 70.2g, Length: 156.4mm, Width (bezel) 23.2mm

Scroll down to the individual light reviews for comparison pics to other lights.

BC008.jpg

BC011.jpg

BC006.jpg


The Backup series build is pretty much what you would expect for this sort of family of lights. The components are generally interchangeable among the family (i.e. common threading and diameters for the heads/tails).

On the whole, they look the most like the Fenix LDx0/PDx0 series lights, but a bit bulkier.

Black anodizing (type III = HA) is glossy black, and lettering is a subdued white against the black background (legible and clear, but not obtrusive). Knurling is not very aggressive, but there are some ridge detail items to help with grip.

Tail threads are anodized at the rear end of the battery tube and the tailcap, allowing for lock-out. The lights can tailstand reliably on my two samples. :)

Clicky switches are the more popular forward clicky type, and look a lot like those found on the recent NiteCore offerings (i.e. silver-plated springs). This later point isn't that surprising, as Jetbeam and NiteCore are now both owned by the same company. Despite being able to tailstand, I found the switches reasonably easy to access, with a typical traverse and feel. :thumbsup:

All lights come with a removable forward-facing pocket clip. Note the clip is not reversible. Clip is fairy basic, but seems sturdy for this type of clip-on model.

BC012.jpg

BC020.jpg


The Backup family comes with the Cree emitter XP-G R5 emitter, with light OP reflector. Reflector is fairly deep, so would I would expect reasonably good throw for these lights, with smooth transition to spill. Emitters were all well centered on my samples. Scroll down to my individual reviews for beamshot comparisons to other lights of their respective classes.

User Interface

The UI will feel familiar to users of the classic Fenix LxT series lights – twist the head tight for Hi, loosen for Lo.

Turn on/off by the forward clicky switch (i.e. press for momentary, click for locked-on).

And that's it. :kiss: No strobe, SOS, etc.

No PWM

There was no sign of PWM by eye or instrument, leading me to conclude these lights are current-controlled.

Testing Method:

Effective November 2010, I have revised my summary tables to match with the current ANSI FL-1 standard for flashlight testing. Please see http://www.sliderule.ca/FL1.htm for a description of the terms used in these tables.

All my runtime graph output numbers are relative for my home-made light box setup, a la Quickbeam's flashlightreviews.com method. You can directly compare all my relative output values from different reviews - i.e. an output value of "10" in one graph is the same as "10" in another. All runtimes are done under a cooling fan, except for any extended run Lo/Min modes (i.e. >12 hours) which are done without cooling.

I have recently devised a method for converting my lightbox relative output values (ROV) to estimated Lumens. See my How to convert Selfbuilt's Lighbox values to Lumens thread for more info.

-------------------

Individual Light Runtime/Output Comparisons

BC10

BC024.jpg

BC016.jpg

From left to right: CR123A, BC10, Thrunite Neutron 1C, 4Sevens Quark Q123, LiteFlux LF3XT, Zebralight SC50, Sunwayman M10R.

All lights are on Hi on RCR (AW Protected where available), about ~0.75 meter from a white wall (with the camera ~1.25 meters back from the wall). Automatic white balance on the camera, to minimize tint differences.

BC10001.jpg

1C001.jpg
Mini123001.jpg


BC10002.jpg

1C002.jpg
Mini123002.jpg


BC10003.jpg

1C003.jpg
Mini123003.jpg


BC10004.jpg

1C004.jpg
Mini123004.jpg


CR-FL1-Summary1-1.gif


CR-FL1-Summary2-1.gif


BC10-HiCR123A.gif

BC10-LoCR123A.gif


BC10-HiRCR.gif


Note for the Hi mode run, I used an unprotected IMR cell due to the apparent high discharge rate. I would estimate that a regular Li-ion RCR would should off well before 20 mins have passed (i.e. definitely >3C discharge rate), which exceeds safe running specs for standard Li-ion.

BC10-LoRCR.gif


-------------------

BA20

BC030.jpg

BC018.jpg

From left to right: Duracell AA, BA20, Fenix LD10-R4, 4Sevens Quark AA-2, Sunwayman M20A, Eagletac P20A2-II.

All lights are on Hi on 2x Eneloop NiMH, about ~0.75 meter from a white wall (with the camera ~1.25 meters back from the wall). Automatic white balance on the camera, to minimize tint differences.

BA20001.jpg
LD20R4-Beam001.jpg

Neutron2A-Beam001.jpg
M20A-Beam001.jpg


BA20002.jpg
LD20R4-Beam002.jpg

Neutron2A-Beam002.jpg
M20A-Beam002.jpg


BA20003.jpg
LD20R4-Beam003.jpg

Neutron2A-Beam003.jpg
M20A-Beam003.jpg


BA20004.jpg
LD20R4-Beam004.jpg

Neutron2A-Beam004.jpg
M20A-Beam004.jpg


2AA-FL1-Summary-1.gif


BA20-HiEne.gif

BA20-LoEne.gif


BA20-HiL91.gif


BA20-HiAlka.gif


-------------------

Summary of Output Levels

A few observations:
  • Regulated output on Hi is extremely bright for an XP-G R5 light - closer to the level of the XM-L based Thrunite Neutron lights than most other XP-G R5 lights I've tested. :eek:oo:
  • Jetbeam's ANSI FL-1 output and runtime estimates seem fairly accurate, for the official battery types supported. Peak throw/beam distance is slightly less on my samples, but not hugely so (i.e. only about 15-20% below spec).
  • The Lo modes of both lights start off at an elevated level (at least twice as bright initially) and then slowly decline to the fully regulated level.
  • The BC10 is direct-drive on 3.7V Li-ion RCR, with much higher initial output levels on both Hi and Lo. Discharge rate on Hi on RCR likely exceeds 3C, so I do not recommend you run the light this way (or use only IMR cells – with the caveat that they are unprotected).

---------------------

Potential Issues

Initial output on Lo is brighter than the final regulated steady-state level (i.e. typically at two to three times as bright initially). Although variable, drop off in output to the lower regulated level is relatively slow (i.e. not noticeable by eye).

Output on 1x3.7V RCR Li-ion on the BC10 is much higher at both levels, and seems to be direct-drive until the regulated level is reached (shortly before the battery protection cut-offs). Discharge rate on Hi exceeds safe discharge rates for standard Li-ion, so I recommend you use only IMR cells if you intend to run it this way (with standard caveat to be careful not to over-discharge, as IMRs do not have protection circuits). But heat would also be a concern at this elevated Hi level.

Clips are not reversible, and are the less reliable clip-on on style (but seem firmer and stiffer than most of this type).

Preliminary Observations

I'll get right to the point – the JetBeam Backup lights appear to live up to their impressive ANSI Fl-1 specs, and handle as you would expect for this type of light. :grin2:

I have a fondness for this kind of simple two-stage mechanism, controlled by head twist (i.e. the classic Fenix LxT series). The build of my two Backup samples are top notch, and the lights seem more sturdy than most. The slightly extra dimensional width also makes it easier to access the slightly recessed forward clicky switch, while still maintaining tailstanding. :thumbsup: Switch feel is good. Knurling is not very aggressive, but I found the lights to be a pleasure to handle and use.

I was a bit surprised initially that they seem able to live up to the rated ANSI FL-1 specs (which are impressive for XP-G R5 lights). As my runtimes show, output on Hi is remarkable for both samples – both for the actual output level, and the regulation/runtime. I don't know how they've did it, but these are the brightest XP-G R5 lights I've ever seen to date. :eek:oo:

Output on Lo is interesting. Both lights start off at higher levels initially (i.e. closer to ~55 estimated lumens), and then slowly drop down to the regulated levels (which are actually closer to ~20 estimated lumens). Although variable on the two modes, the decline is nevertheless slow enough that will you not notice it by eye. As a result, the FL-1 estimates of 30 lumens are a bit on the low side, but not unreasonable (i.e. FL-1 states that output is measured at 3 mins into the run). The regulated ~20 lumen Lo level explains part of why they are able to maintain such extended runtimes. But even at these levels, the efficiency of the lights exceeds what I would expect from a XP-G R5. :twothumbs

The BC10 is direct-drive on 1x3.7V Li-ion, with much greater initial output at both levels (i.e. 470/210 estimated FL-1 lumens, versus of 255/36 on 1xCR123A :eek:oo:). Given the high >3C discharge rate at the Hi level, I strongly recommend you don't run the light this way on regular Li-ion RCR. You could run it on Hi on an IMR cell, but I also worry about heat build-up at these sorts of drive levels (and with the warning that IMR cells are not protected, so be careful not to run them down).

Beam pattern is good, with a decent sized hotspot with good transition to spill. Throw and spillbeam width are fairly typical for this size light.

Like a number of other "family" series lights, I presume comparable circuits/heads are being used between the 1xCR123A, 1xAA and 2xAA models.

To sum up, the Backup series lights are well-designed, easy-to-use, two-stage lights with a good, balanced beam pattern – but with much higher output on Hi than I've seen before for this emitter type. Runtimes are also excellent at both levels, especially on Lo. A nice series of lights at attractive prices, I am sure these will do well for JetBeam. :)

UPDATE MAY 13, 2011: I have just reviewed the JetBeam BC40 here - a new high-output, XM-L-based, 2x18650/4xCR123A member of the Backup family.

UPDATE JUNE 7, 2011: A user has just reported a 12 min runtime on protected RCR on the BC10, indicating a 5C discharge rate. This is not safe for standard Li-ion chemistry, and should not be used. Only IMR cells can handle these sorts of discharge rates (but the lack of protection circuits means you have to be very careful not to run down the cells, or you will permanently damage them). Be safe. :candle:

----

BC10 and BA20 provided by JetBeam for review.
 
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AardvarkSagus

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Excellent review as always Selfbuilt. I continue to enjoy seeing our observations line up so well. I was unaware of the gradual drop in low level brightness (a testament to its unnoticeable nature). Yes, the little BC10 is quite the pocket powerhouse. My wife actually stole mine as soon as I was done with it.
 

HIDblue

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Great review selfbuilt! Did you need to use a spacer with the AW RCR123 for it to make contact? I've heard some folks were having problems due to the reverse polarity protection ring on the + side of the light.
 

Bass

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Excellent review. These look like a great series of lights; better than I expected and at a keen price point.

Seems Sysmax are pitching the Jetbeam brand at the lower end (price wise) and making Nitecore the premium brand of the two.
 

selfbuilt

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Great review selfbuilt! Did you need to use a spacer with the AW RCR123 for it to make contact? I've heard some folks were having problems due to the reverse polarity protection ring on the + side of the light.
No problems with any of my AW protected RCR or AW IMR cells - all worked fine.

As an aside, I think these would be good lights to try 3V LiFeP04 cells in, due to the lower nominal voltage (but I don't have any to try).
 
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HIDblue

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

No problems with any of my AW protected RCR or AW IMR cells - all worked fine.

As an aside, I think these would be good lights to try 3V LiFeP04 cells in, due to the lower nominal voltage (but I don't have any to try).

Thanks for the info selfbuilt.
 

justlux

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Jetbeam BC10 7,000 lux on a single AW RCR protected cell, that is very impressive. Please could you confirm that it is 7,000 lux and not just a typing mistake?
 

selfbuilt

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Jetbeam BC10 7,000 lux on a single AW RCR protected cell, that is very impressive. Please could you confirm that it is 7,000 lux and not just a typing mistake?
It is not a typo - and it shouldn't be surprising, as the output on RCR is more thn 40% higher than CR123A. Remember that lux is a non-linear scale, so you need to compare square-roots to make linear comparisons of relative throw (i.e. the beam distance column). 7000 lux translates into just under 40% more throw, as correctly illustrated by beam distance measures.

But again, I would counsel that heat and discharge rates are going to be issues at this drive level on 3.7V Li-ion.
 

MichaelW

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Plans for a review of the BA10 & BC20?
I want to see how the better siblings perform.
 

selfbuilt

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Plans for a review of the BA10 & BC20?
I want to see how the better siblings perform.
Sorry, no plans to. I am trying to limit the number of samples I test from any given series (e.g. same with the Klarus, etc). Hard to find the time with all the requests I get.
 

sirimaxi

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Excellent review Selfbuilt as usual!!! You know based on the PM we shared that I was waiting this review to pull the trigger and that's what I did yesterday after reading your review...I have a 3V LiFeP04 cell so I let you know what the results I get when I receive the light. Going to the details of the review...Can you clarify this: On the photo of the BC10 comparing to other lights you showed there the 4sevens Quark 123 but on the beamshots you put Mini 123...That's a typo? beamshot shown is from the Quark 123 or Quark Mini 123? This same thing happens on your Neutron 1C review. Another question: Do you know if this light has over-discharge protection to protect IMR batteries?

Thanks!!!!!
 

selfbuilt

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Can you clarify this: On the photo of the BC10 comparing to other lights you showed there the 4sevens Quark 123 but on the beamshots you put Mini 123...That's a typo? beamshot shown is from the Quark 123 or Quark Mini 123? This same thing happens on your Neutron 1C review.
Yes, those are not typos. The various pics and analyses are designed to facilitate different types of comparisons. For the body height comparisons, I pick popular lights of the same class with similar builds, to allow you to judge the relative size comparisons (i.e. it may look like a Quark, but are the dimensions really the same?).

For the beampics, I choose lights that use the same emitter class and output bin (if possible). All my Quarks are the earlier XP-E R2 versions, which are quite different in beam profle from the current XP-G R5/S2 (but the body style hasn't changed, hence my use of them above). The Mini is used in the beampic and runtime comparisons instead, as my sample is an XP-G R5.

You also need to consider the practicality of how I do my reviews. I don't know which runtimes will be the most appropriate comparison until I do ALL the testing - but I don't wait until the very end of testing to start taking pics, as that would be more time consuming and inefficient.

Frankly, I get a little frustrated with some of the comments I receive on this issue (i.e. manufacturers complaining that their particular light wasn't chosen is some pic on some specific later review, etc.). I am sorely tempted to scrap doing those pics, given the hassle. But I figure it is a useful dimensional comparison for people.

Another question: Do you know if this light has over-discharge protection to protect IMR batteries?
I can confirm that is does not. At the point where I stopped the IMR run (i.e. the run-away point pass the regulated level), by battery was ruined at <2V resting. I recommend you scrap any battery that gets depleted below ~2.5V or so, even temporarily. Although they may recover with time to >3V levels, I wouldn't trust these cells. This is the danger of using unprotected cells in regulated LED lights - by the time you notice significant dimming, the cell has been irrevocably damaged and needs to be discarded.
 
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sirimaxi

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Selfbuilt, Thanks for the explanation...I just thought you were comparing body+beamshots between each brand...now it's clear for me...I love the body height comparison because it gives a very good approach between each model...don't worry about complains, no matter what good you are, someone will complain something...keep going in the direction you are!!!! Thanks!
 

dannstrait

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Ho-hum, just another fantastic review by Selfbuilt! After reading the review, I was reminded of this post by UnknownVT. Do you think there is significant risk running on Li-ion, especially if you happen to get a light with a low Vf?
 

selfbuilt

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Do you think there is significant risk running on Li-ion, especially if you happen to get a light with a low Vf?
Short answer, yes. That's why I don't generally recommend running Li-ion on lights that are direct-drive at high levels (i.e. boost-only, no buck). There is a risk of damaging the emitter over time (and potentially more quickly through thermal runaway).

But how practical are those risks versus how theoretical? There doesn't seem to be a lot of reporting of emitter failure on boost-only lights on Li-ion (but that doesn't mean it isn't happening, though). The battery and emitter experts here would be in a far better position to weigh in on the issue. I honestly don't know how great the risk is, but I have assume there is some degree of one.
 

candle lamp

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Output on 1x3.7V RCR Li-ion on the BC10 is much higher at both levels, and seems to be direct-drive until the regulated level is reached (shortly before the battery protection cut-offs). Discharge rate on Hi may exceed safe discharge rates for standard Li-ion, so recommend you use IMR cells if you intend to run it this way. But heat would also be a concern at this elevated Hi level.

Many thanks for your excellent & detailed review as usual. :wave:
Do you mean that it's available to use a protected RCR123A Li-ion cell to BC10 or do you recommend to use IMR cell only?

Best regards,
 
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MichaelW

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Do you mean that it's available to use a protected RCR123A Li-ion cell to BC10 or do you recommend to use IMR cell only?

I think that means use LiFePO4 (IFR) cells as your usable workable recharge solution.
ICR & IMR are being pushed towards funtime only. There seems to be a shift toward lower voltage; QMiniX, Xeno X03, this.

Although, what happened to the cells that knock down their output to an even 3 volts?
 

selfbuilt

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Do you mean that it's available to use a protected RCR123A Li-ion cell to BC10 or do you recommend to use IMR cell only?
I never actually "recommend" (full stop) use of non-protected cells, except in lights where there are built-in circuit low-voltage protection features. In this context, I "recommended" IMR only if you intended to run 3.7V Li-ion on Hi. I think this is a bad idea, given the heat produced, but I know a lot of people will be attracted to it for the insanely high output. Knowing that tendency here, :rolleyes: I wanted to counsel use of IMR cells only in that situation, as the discharge rate would be unsafe for regular Li-ion.

Frankly, I think 3V LiFePO4 would be a much better idea (but don't actually have any on hand to test at the moment). I fully expect the light will not be as bright on these cells (i.e. closer to 3V CR123A). Which brings us back full circle to people wanting the most output possible and 3.7V Li-ion, etc., etc.
 

candle lamp

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

I think that means use LiFePO4 (IFR) cells as your usable workable recharge solution.
ICR & IMR are being pushed towards funtime only. There seems to be a shift toward lower voltage; QMiniX, Xeno X03, this.

Although, what happened to the cells that knock down their output to an even 3 volts?

I never actually "recommend" (full stop) use of non-protected cells, except in lights where there are built-in circuit low-voltage protection features. In this context, I "recommended" IMR only if you intended to run 3.7V Li-ion on Hi. I think this is a bad idea, given the heat produced, but I know a lot of people will be attracted to it for the insanely high output. Knowing that tendency here, :rolleyes: I wanted to counsel use of IMR cells only in that situation, as the discharge rate would be unsafe for regular Li-ion.

Frankly, I think 3V LiFePO4 would be a much better idea (but don't actually have any on hand to test at the moment). I fully expect the light will not be as bright on these cells (i.e. closer to 3V CR123A). Which brings us back full circle to people wanting the most output possible and 3.7V Li-ion, etc., etc.

Thanks for your reply. MichaelW, Selfbuilt :)
 

cubegleamer

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Re: JetBeam Backup Series (XP-G R5) BC10 & BA20 Reviews: RUNTIMES, BEAMSHOTS, and mor

Thanks for the review. I just got the BC10 based on your info. It's a great light and my first cr123.
 
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