Warning: even more pic heavy than usual.
The 3xAA GX25A3 is the little brother of the 6xAA SX25A6 that I recently reviewed from Eagletac. Although tiny, this light packs a lot of punch for the size – let's see how it does against the other multiple-AA lights.
Manufacturer Reported Specifications:
(note: as always, these are simply what the manufacturer provides – scroll down to see my actual testing results).
- LED: Cool White CREE XM-L2 U2 LED
- Four brightness levels (Regular mode): ANSI FL-1 lumen: 915-832/301/9
- Runtime: 1.3/3/100+ hours
- Two brightness levels (Tactical mode): ANSI lumen: 915-832/185/Strobe
- Runtime: 1.3/5 hours
- Center lux: 20,100 lux
- Center spot angle: 6°
- Spill light angle: 57°
- Beam distance: 311 yards / 284 meters
- Battery Type: 3xAA, 1.5V alkaline/lithium,1.2V NiMH, or 3.7V li-ion
- Compatible battery diameter/length: Diameter: 14-14.6mm, Length: 50-50.5mm
- Lens: Waterwhite glass lens w/ harden treatment, Anti-reflective (AR) coating on both side (96% transparency)
- Reflector: Smooth aluminum reflector
- Material: HAIII hard anodization aerospace aluminum
- Waterproof: IPX-8 standard
- Innovative slot load design, No battery tray or battery magazine needed
- Seven hidden auxiliary outputs: Strobe/Strobe(Var)/Flash(Hi)/S.O.S.(Fast)/S.O.S./Becaon/Flash(Lo)
- Dimensions: Head Dia.1.5 inches (47 mm), Body Dia.1.4 inches (36 mm), Length:4.3 inches (173 mm)
- Weight:5.2 ounces (260 grams)
- What's Included: GX25A3 flashlight, Spare o-rings, User Manual, Mil-Spec Para-cord Lanyard w/ quick attachment clip, Tailcap with rear switch, Extra signal connection through the body tube (pre-installed), Heavy Duty Nylon Holster w/ self-retention device and open-top design
- MSRP: ~$95
Unlike the SX25A6 (which featured the new Eagletac packaging with the light in a soft fabric pouch with a drawstring), the GX25A3 came in the traditional Eagletac box. Included accessories are a wrist lanyard, extra tailcap (with secondary switch), belt holster, extra o-rings, manual, and warranty card.
Note that the standard flat tailcap is installed for all the measures and pics below.
From left to right: Duracell NiMH; Eagletac GX25A3; Nitecore EA4; Sunwayman D40Al Olight S35; Eagletac SX25A6.
All dimensions directly measured, and given with no batteries installed (unless indicated):
Eagletac GX25A3 3xAA: Weight: 151.4g, Length: 109.2mm, Weight (bezel): 38.6mm
Eagletac SX25A6 6xAA: Weight: 279.8g, Length: 183mm, Weight (bezel): 47.0mm
Fenix TK45 8xAA: Weight: 307.3g, Length: 202mm, Width (bezel) 50.6mm, Width (tailcap) 44.0
ITP A6 6xAA: Weight: 209.9g, Length: 174mm, Width (bezel) 48.0mm, Width (tailcap) 37.8mm
JetBeam PA40 4xAA: Weight: 184.0g, Length: 183mm, Width: 40.8mm (bezel), 42.1mm (max width)
Lumintop PK30 6xAA: Weight: 454.0g, Length: 218mm, Width (bezel): 62.0mm
Nitecore EA4 4xAA: Weight: 161.6g , Length: 117.9mm, Width (bezel): 40.2mm
Nitecore EA8 8xAA: Weight: 301.9g , Length: 182mm, Width (bezel): 60.1mm
Olight S35 3xAA: Weight 177.3g, Length: 127.7mm, Width (bezel): 38.7mm
Olight S65 6xAA: Weight 215.4g, Length: 180mm, Width (bezel): 38.7mm
Sunwayman D40A 4xAA: Weight: 167.9g, Length: 120.4mm, Weight (bezel): 40.0mm
Sunwayman M40A 4xAA: Weight: 247.0g , Length: 145mm, Width 57.0mm (bezel)
The GX25A3 is the smallest 3xAA light I've seen so far.
The overall build of the GX25A3 is basically a smaller version of the 6xAA SX25A6, and is very reminiscent of some of the other recent Eagletac lights (e.g., TX25C2 and GX/SX/MX25L2).
Hand feel is good (for all size hands), and the light is comfortable to hold and use. Grip is reasonably good, thanks to all the build elements. Knurling is somewhat mild, but is present over the entire battery tube/handle. As with the SX25A6, there are also finger well cut-outs on three sides of the battery tube.
Anodizing is glossy black, hard anodized (i.e., type III), with no obvious chips or damage on my sample. Labels are bright and clear (i.e., sharp white against the black background).
Like the SX25A6, the GX25A3 doesn't use a battery carrier, but instead has cut-out wells for the cells. The cells are arranged in continuous series, with connection being made by contacts on a connector piece in the tailcap. This connector can spin freely, and locks in place to a couple of holes in the body that line up with rods in the tailcap.
Screw threading on the tailcap is traditional triangular cut, and is anodized. This actually allows you to lock out the light, as there is a signal that carries through the tailcap. On most other lights with this sort of battery arrangement, tension on the springs determines the contact, and hence no lock-out is possible.
The GX25A3 can tailstand, even with the secondary tailcap switch installed. This special tailcap is bundled with the light, and the switch functions exactly the same as the main switch.
Screw threads are square-cut (and thick) in the head region where mode switching occurs, as with the other recent Eagletac lights
With either tailcap installed, the electronic switch controls on-off, with output mode selection and programming controlled by head twist. This is the same as the other recent GX/SX/MX25L2 and TX25C2 lights – they all use a distinctive set of contact points in the head, required for mode switching (scroll down for a UI discussion).
Side-switch feel is good for an electronic switch – there is a reasonable traverse, and the action is firm. Grip is good with the texturized rubber button cover. The secondary tailcap switch on the kit version has a similar feel and function, but is recessed for tailstanding.
The GX25A3 reflector is smooth and surprisingly deep – this should translate into very good throw for the size. Overall reflector dimensions remind me of the Nitecore EA4 and Sunwayman D40A. The XM-L2 emitter was well centered.
The light has a flat black aluminum bezel.
The interface is identical to my SX26A6 – in fact, they share the same manual. Turn the light on/off by the electronic switch. Press and hold for momentary, press-release (i.e. click) for locked-on.
There are three output levels controlled by how loose/tight the head is (i.e., the three levels are accessed in sequence from head fully tight). As soon as you loosen past fully tight, you drop down to the second level. You drop down again to the third (and final) level after a ~120 degree turn. This is the same as the TX25C2, but differs from the G25C2 and GX/SX/MX25L2 series lights (that offer four modes instead). You need to do at least one and a quarter full head turns from tight to get the light to shut off (but you can easily lock out the light at the tailcap).
There are two possible groups of output modes available - Tactical (100% > 15% > Strobe, in sequence) and Regular (100% > 40% > 0.5%, in sequence). You can switch between the two groups by turning the light on max (fully tight) and loosening the head to the second level and then back to tight, repeating this sequence ten times in five seconds.
A new feature on these recent tactical lights is the ability to rapidly access a momentary Turbo from any head position by a press-and-hold of the switch when On. You can similarly access strobe at any time by a double press and hold (i.e. click and press-hold). Simply release the switch to return to your previous head-set level.
To access the hidden auxiliary modes, do a quick loosen-tighten twist of the head (from first level tight to third level and back again). Repeat this twist to advance through the modes. Mode sequence is: Strobe I > Strobe II > Hi-Flash > SOS I > SOS II > Beacon > Lo-Flash, in repeating sequence. Turn off the light or loosen the head to quit the hidden modes. I will describe these modes in more detail below.
There is an "energy saving feature" where the light reduces output by 25% after 200 seconds in Turbo. You can toggle this feature "off", which results in a 10% step-down instead. See my runtime results below for more information. To toggle this feature off or on, turn the light on at the third level, and switch back and forth to the second level for ten times in five seconds.
For more information on the light, including the build and user interface, please see my video overview:
Video was recorded in 720p, but YouTube typically defaults to 360p. Once the video is running, you can click on the configuration settings icon and select the higher 480p to 720p options. You can also run full-screen.
As with all my videos, I recommend you have annotations turned on. I commonly update the commentary with additional information or clarifications before publicly releasing the video.
There is no sign of PWM that I can see, at any output level – I believe the light is current-controlled.
My GX25A3 is again identical to my SX25A6 – and both are similar to my TX25C2 and GX/SX25L2 in terms of the auxiliary blinking modes.
The main strobe is standard high frequency strobe, measured at 9.6 Hz on my GX25A3.
The second strobe mode is an alternating or "oscillating" strobe, switching between 6.5Hz and 15.2Hz every 2 seconds.
Hi-Flash is basically a full power slow strobe/beacon mode. Frequency was a reasonable ~1.6Hz. Note that the deflection spikes you see above are just the on and off signals of the pulse (i.e., it spends roughly half the time on, half the time off, with each pulse).
The "fast" SOS signals the full SOS sequence (dot-dot-dot, dash-dash-dash, dot-dot-dot) in just under 3 secs. Note again that the traces above refer to both the on- and off-signal for each pulse of light.
In contrast, the "slow" SOS takes just under 3 seconds just do the "S" (i.e. dot-dot-dot), and about 4 second to do the "O" (i.e., dash-dash-dash), with a good 3 seconds in-between each Morse code letter. Personally, this seems far more useful than the rather frenetic initial SOS mode.
Beacon is a slow full output flash (almost 2 secs long), re-occurring approximately every ~14 secs (i.e., a very slow beacon)
A standby current drain is inevitable on this light, due to the electronic switch in the head (and/or tailcap). I have measured it on my GX25A3 to be 78uA. Given the serial cell arrangement, would translate into just under 3 years on 2000mAh NiMH.
If you are concerned about this minute drain, you can easily lock-out the GX25A3 by a quick twist of the tailcap.
And now the white-wall beamshots. All lights are on Sanyo Eneloop NiMH, at the maximum supported number for the given models (4x, 6x or 8x). Lights are 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 (i.e., my SX25A6 sample is a neutral white tint, but you won't be able to tell that below).
Simply put, the GX25A3 beam pattern looks very similar to the beam of the Nitecore EA4, but is a touch "throwier". The Sunwayman D40A is pretty close as well to the GX25A3. These lights all have remarkably good throw for their size.
The main difference of the GX25A3 to the SX25A6 is the slightly narrower spillbeam on the 6xAA model, and slightly greater throw (both to be expected, due to the larger reflector on that light). GX25A3 max output doesn't seem that much less than the SX25A6 though … scroll down to my summary tables for direct measures.
For outdoor beamshots, these are all done in the style of my earlier 100-yard round-up review. Please see that thread for a discussion of the topography (i.e. the road dips in the distance, to better show you the corona in the mid-ground).
FYI, any "streaks" you see across the images are bug-trails. Flying insects are often attracted to the bright lights, and their flight trails get captured as swirly streaks due to the long exposure time.
As expected, the SX25A6 definitely has better throw at a distance – with a more pronounced hotspot.
There really isn't much of a difference in throw between the GX25A3 and D40A, despite what is shown above. It must be my variable hotspot placement on this shot.
All my output numbers are relative for my home-made light box setup, as described on my flashlightreviews.ca website. 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 devised a method for converting my lightbox relative output values (ROV) to estimated Lumens. See my How to convert Selfbuilt's Lightbox values to Lumens thread for more info.
Throw/Output Summary Chart:
My summary tables are reported in a manner consistent with the ANSI FL-1 standard for flashlight testing. Please see http://www.flashlightreviews.ca/FL1.htm for a discussion, and a description of all the terms used in these tables. Effective July 2012, I have updated all my Peak Intensity/Beam Distance measures with a NIST-certified Extech EA31 lightmeter (orange highlights).
As you can see, despite its small size, the GX25A3 is no slouch when it comes to output and throw. Although not quite in the same throw category as the 6xAA SX25A6, output is pretty close. In fact, it has one of the brightest turbo modes among all my 3x/4x AA lights.
Let's see how my output estimates compare to the official Eagletac specs for this light:
Again, very close. Note that the step-down value shown above is when you have this featured "disabled" (which actually produces a ~10% drop in output, instead of the standard ~25%). With the default 25% step-down in place, I estimate ~620 lumens after step-down.
Note: in terms of the runtimes, "Hi" is 100%, "Med" is 40%, and "Lo" is the 15% output mode.
As you can tell from above, Eagletac is using a good current-controlled circuit in the light – runtimes are excellent, especially for only 3xAA. It's true the light won't last quite as long as some of the good recent 4xAA lights, but this is an impressive showing on 3xAA.
Like the SX25A6, the default for the GX25A3 is to step down ~25% after 200 secs on Hi. With this feature "disabled", there is a smaller ~10% drop. In either case, the light remains in generally flat regulation for a good part of the run – which is impressive for just 3xAA.
I don't have a lot of comparator data to other lights on L91 lithiums, but here is the GX25A3 compared to NiMH (Eneloop):
The GX25A3 runs on L91 lithiums, but with slightly decreased initial Turbo output. I would estimate that the ANSI FL-1 output level to be ~770 lumens (compared to ~910 on Eneloop).
Also, as with the SX25A6, the main LED begins to flash as standard primary batteries drain down. For alkaliine on the GX25A3, this essentially means soon after the light starts fall out of regulation. Note that this was mainly for alkalines - no real sign of it on NiMH, and L91 didn't show it until much later (when output was already quite low).
Let's see how the max output of the GX25A3 compares to some of the 6x and 8xAA lights:
The GX25A3 is right up there with many of the recent 6x/8xAA lights, in terms of initial max output. As expected, the GX25A3 won't run for as long on 3xAA cells. But it goes to show you how far the 3x/4xAA class has come.
In terms of comparison to the SX25A6, the main advantages of that larger light are extra runtime and throw.
As before, Eagletac's ANSI FL-1 runtime specs are generally consistent with my results. Recall that the FL-1 standard calls for time to 10% output (not 50%, as reported above), and that I am using relative low-capacity 2000mAh Sanyo Eneloop.
Surprisingly, the GX25A3 will also take 3x14500:
As you can see though, the light is no brighter on 3x3.7V Li-ion - the regulated levels are the same. Runtime is similarly not that different from standard NiMH Eneloop. The reason for this is that you have to consider the voltage when doing capacity conversions (i.e., Work-hours = Amp-hours * Voltage). By that measure, the actual capacity to do work is not that different between a 750mAh 14500 and 2000mAh Eneloop.
As with other Eagletac models where output mode is set by the degree the head is tightened, you need to keep all contact surfaces in the head scrupulously clean. Long-term reliability of the switching mechanism/pins is unknown.
Similar to the SX25A6, mode spacing is a bit unusual, with only three levels per group and no typical "Lo" mode (i.e., you basically get to choose between Turbo > Hi > Lo, or Turbo > Med > Strobe). See my lumen estimates above for more info.
Due to the electronic switch in the head, there is a standby current when the tailcap is fully connected. This is relatively small however (i.e., would take almost 3 years to completely drain NiMH on its own).
Light starts flashing on alkalines once it falls out of regulation (which is very quickly, on the Hi/Turbo).
Light lacks any sort of anti-roll feature, and can roll fairly easily.
Light can support 3x14500 Li-ion (3.7V), but the early production runs may not be able to fit protected cells (e.g., my protected AW 14500s were too tall to allow the tailcap to screw down sufficiently). Eagletac has revised this, and currently shipping lights can handle all length cells.
The GX25A3 is an excellent little 3xAA flashlight, with many of the same features as the "big brother" 6xAA SX25A6 that I recently reviewed.
Overall build and user interface is basically the same as the SX25A6, just in a smaller 3xAA format. The SX25A6 has a wider head for greater throw, but overall output levels are not that dissimilar between the models. I've noticed this for other lights in the 3x/4X class – double the number of AA cell typically nets you mainly more runtime (with extended regulation).
I personally like the interface for the GX25A3/SX25A6 (i.e., electronic side-switch for Off/On and head-twist for setting output levels). A nice touch here is that the GX25A3 comes by default with both the standard flat tailcap, and the alternate tailcap with a secondary On/Off switch. For the SX25A6, you need to buy the kit version to get this switch tailcap. Note the alternate tailcap switch exactly duplicates the function of the regular side switch.
That said, I know not everyone is a fan of using a head-twist for output level setting – but it does give you the advantage of being able to predict your output level before turning on. That said, I do miss the 4-levels of the G25C2 family, and mode spacing on the 3-level GX25A3/SX25A6 is not ideal for me (i.e., you really only have the choice between Turbo > Hi > Lo, or Turbo > Med > Strobe on these lights).
The GX25A3 does share the same kind of excellent output/runtime efficiency as other members of the Eagletac family. That said, don't expect regulated output on Turbo for very long on just three alkalines. Also, as with the SX25A6, expect to see low voltage warning flashes once alkalkine cells drop out of regulation. As such, I would say this light is really best suited to NiMH or L91 (or limiting alkalines to the lower output modes). Interestingly, the GX25A3 even supports 14500 Li-ion (although that won't net you any greater output or runtime over NiMH Eneloops).
Beam pattern is very nice, with excellent throw and output for the size. On both measures, this light tops my larger 4xAA Nitecore EA4 (although the difference isn't really noticeable in practice).
It took awhile for Eagletac to send this light to me for review – apparently, they were having a hard time keeping inventory. And I can understand why it would be popular – you get a lot of light here, despite the diminutive size. Build quality is excellent, and it is not a surprise to me that it would command a price premium over the Nitecore EA4. As always, it's really a question of the user interface and feature set you are looking for – a worthy addition to the 3x/4xAA class.
GX25A3 was provided by Eagletac for review.