Review: JETBeam SRA40 (XM-L2 T6, 4x AA)

Battery: 4x AA
Modes: 5 (Low- Medium-High / Strobe - SOS) with memory.
Switch: Head double switch.
Date: November 2013

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The new Jetbeam proposal complements the existing offer in the field of high performance flashlights that use common batteries, regardless of the power of the Li -Ion batteries. Nitecore popularized the format with the launch of the EA4, some time ago. Sunwayman then presented its alternative, the D40A. Now Jetbeam launch this SRA40, similar to the previous two lights, which is presented as the “Rechargeable Almighty King”. The least interesting!

The main characteristic of this SRA40 facing against competition lies in a larger optics and its own built-in charging port, through which we can charge NiMH batteries without removing them from the flashlight.

The light arrives presented in a blister pack in which the flashlight can be seen on both sides without being opened. In the cardboard surrounding the flashlight you can read the main features of the product, such as some ANSI / NEMA FL1 values.

The blister is deployed on two sheets joined at the base, so it is not necessary to cut the blister to remove this flashlight. Inside, next to the lantern we find instruction manual, warranty card, certificate of authenticity, wrist strap, a gasket parts, and adapter for recharging.

The adapter is modular. Thus Jetbeam has solved the problem of having to make adapters for the different regions and include only the area corresponding to each module. As you can see, in my case included making Jetbeam type EUR.

The first sensation that this SRA40 gives when out of the blister is solidness. It feels good in hand as a piece, weighing and pretty nice size.

Anodizing has a particular tone, a uniform dark gray and very nice matte finish.

It is perfectly machined, with exquisite precision from all angles and edges. It has several engravings on it, as the logo / model and a warning on the use of NiMH batteries in the body, or a serial number next to the hot surface warning on the bezel.
The SRA40 is built on a single block, like the EA4. This means that the only detachable part is the tail cap, whereby replace batteries. The bezel seems to be sealed, although due high precision machining it is difficult to notice the joint.

The flashlight head has a substantially diameter greater than the body, which gives you extra grip, allowing to take up the torch head left outside our fist easily and intuitively. The sides of the head are provided with discrete dissipating fins. In the frontal plane have a small metal tray that provides the framework for the two switch buttons. These buttons are arranged one above the other and have different shapes, making it easy to identify by touch in the dark. On the opposite side, we have the charging port. This port does not have any rubber cover or similar, but looks internally insulated.

The optics of this Jetbeam is awesome. A huge anti –reflective coated glass lens protects an immaculate smooth reflector with relatively large diameter and deep. XM -L2 is assembled with a centering mechanism in black, ensuring perfect positioning within the optical assembly.

Compared to EA4 this SRA40 far exceeds the dimensions of its optical, so hopefully will do so with its throw.

The battery arrangement is 2S2P, and the accommodation is directly machined in the light block. The contacts clearly indicate the correct placement of the batteries and inside the barrel can also see the marks for correct polarity of the battery pack. The tailcap, inside has a rotary contact plate with two side points for proper centering of this during installation.

Threads are completely anodized, as the body of the flashlight is not conductive. The machining of these is just nice, and came lightly greased factory.

The tailcap has a design that allows us to place the SRA40 in solid tailstand, even with the lanyard installed, thanks to three pierced battlements that surround its base. In the center , we find a threaded hole in order to install a glass breaker punch as seen in other models of the brand, and also allows to install the flashlight on a tripod because the thread is compatible with 1/4- 20UNC standard. This is really useful if you want to use the flashlight as a portable lantern.

Jetbeam has given the SRA40 a simple repertoire of modes. It has three main modes, High-Medium –Low, with memory.
By employing a dual switch system, we control the on/off with the round button, and change modes with the square button. The flashlight recalls that mode has been employed for the last time before it turns off and even after replacing the batteries (i.e. breaking the circuit). The modes arrangement is from high to low, being the low mode the last of the sequence.

We also have two hidden auxiliary modes. Access to strobe mode is quick and easy access, just holding the power (round) button for more than two seconds, either with the flashlight on or off. The second hidden mode, the SOS sequence is accessible by keeping the mode button (square) for more than two seconds with the flashlight on. None of these two auxiliary modes has memory, so if you turn off the SRA40 in any of them, next on will return to the last mode used on the main sequence.

In addition to this mode sequence, there are other two “embedded” modes inside High mode, which are to the flashlight automatically, steps down after continued usage. Later delve into it.
The square button for changing modes has under its rubber shell two small blue LEDs that acts as charge indicator: By clicking on it with the flashlight off, it displays the charge status of the batteries using three different sequences. The two blue LEDs steady mean load (close) to 100, a single blue LED is 50, and if the bottom LED flashes it indicates you have to recharge the batteries. These signals come into play automatically every time we turn on or change of mode flashlight, showing the state by these signals during the first 5 seconds of use.

These emitted light codes by the secondary button also function as automatic charge indicator thanks to the flashlight monitors the state of charge and automatically shows the appropriate signal in the secondary button about every 10 seconds when on.
Finally, the flashlight has an integrated port for charging NiMH batteries, without removing the AA batteries from the flashlight. This system has an “own” port on the side, that recharges the AA batteries in series. The charge current is set to 350mA, somewhat slow especially if we use high capacity batteries. The flashlight shows the state of charge through the blue LEDs of the mode switch. While the charge is active, the two LEDs flash alternately, and once the charge is done they come steady.

Here we can see how the distribution of the intensities of the different modes. I added, just for information, the two stepdown outputs the flashlight automatically accessed during continuous use of the High mode. More details below.

When reading only three modes in the specifications submitted by the manufacturer, with one big difference between the High and Medium mode so as we could guess that the Jetbeam SRA40 had implemented some sort of stepdown to close that big gap. After the usual test in the integrating sphere I have found that there are two stepdows instead of one, scheduled by time.

The first drop kicks in after 3 minutes of continuous use High mode, where the flashlight gives a small slump, but still perceptible to the naked eye, from the initial over 900LM to about 640LM. Ten minutes later , the light returns to drop its output to stabilize around 435 Lumen, which will remain stable for the rest of life of the batteries , as long as we don’t change modes as it will restart the timed sequence. Another important detail noted in the test is that , once the batteries are agonizing, the SRA40 gives again a stepdown, to Low mode , where thanks to the moderate current drain thus is able to continue to operate stably almost an hour and a half more, then fell off gradually reducing output regulation without being completely off.
In the chart below we compare the performance curve SRA40 competing against some other single XM-L lights with similar specs:

First, clarify that the curve EA4 CW (*) is rescaled from EA4W because unfortunately I do not have a Pioneer CW unit. What I’ve done is add the percentage of missing LM to the curve obtained after the test of my EA4W (NW) to match the maximum of the P25, since both lights share optics and are specs. Take these values, the EA4 CW simply as a rough reference.
We see that it looks as if the flashlights manufacturers had agreed to match the intensity which their contenders falls after the stepdown, coinciding in all except the rescaled EA4 CW . We also see like the SRA40 , while more powerful in the first step and provided with a non-existent second step in EA4 is able to scrape about 15 minutes regulated output in the third step , to maintain control in low mode . The P25 Nitecore, just added for the sake of curiosity, shows a similar regulation, with several intermediate steps, but being powered by an 18650 not playing in the same league, although they have very similar performance.

Finally, as a curiosity, I have documented a phenomenon that I could see while performing the test SRA40. As I said earlier, SRA40 shows automatically using LEDs his side push the state of battery charge. When observing the screen od the digital multimeter by which I perform datalog for subsequent conversion to LM, could warn that, about every 10 seconds, the output of the flashlight had a slight slump for a second. After observing the lantern I saw that tiny drop in reading coincided in time with the signal emitted by the secondary button, meaning the flashlight accused slightly on the two little blue button LEDs. Obviously, it’s totally not noticeable by the human eye and I’ve only been documented thanks to the incredibly high sensitivity of the setup of the integrating sphere. To show this, I had to expand a section 200 seconds of data, adjusting the Y axis (Lumen) to 0.2LM intervals, and the X (time) axis in seconds instead of minutes.

As expected, especially for the larger diameter of the reflector and also the improved and more powerful emitter equipped, the projection SRA40 offers a much more thrower than the Nitecore EA4 and its family. Jetbeam specs a maximum throw of 390 meters thanks to 38,000 candelas.

The XM-L2 T6 is CW, and is free from greenish hues. You can notice a little chromatic aberration in the corona around the hotspot, yellowish, something we have already seen in countless lights equipping CREE powerleds. This effect is more pronounced in the low mode, as the lantern seems to have adjusted to current modes. Anyway, the change of color in the area of the projection is not overly visible in outdoors common use or away from the white walls.

In general, SRA40 projection provides more overall light and throw than its competitor Nitecore EA4, by two key factors: The larger diameter and dimensions of the reflector and smooth using an XM- L2 of the second generation. Still, Jetbeam has managed to maintain a good spill light that makes this flashlight in an all- terrain suitable for any use.
Below I offer some exterior shots obtained after comparing the SRA40 against some lanterns similar features, all in maximum performance mode.

The scenario is a small flat in which, about 120 meters from our position, a group of pine trees is surrounded by wild weeds. As you can see in the control picture, there is enough light pollution from the nearby airport of El Prat, and very high humidity in the air painting the flashlights beams, scribbling somewhat the subject. I must also apologize for the blurriness of the shot with the Rofis TR31C, due to a sudden wind blow destabilizing the tripod and not being noticed until reviewing shots on the PC monitor.

Let us now concentrate, as far as possible from high humidity to focus on the scope, comparing the magnified area in the following sequence:

It is easy to see that the SRA40 , with its greater diameter reflector and new generation CREE emitter it’s on top of the competitors , and offers a balanced projection without neglecting the important flood light as useful as in open spaces in which we found .

Negatives: The first thing that struck me about this SRA40 is the use of an “own” type connector for battery charging. With the popularization of smartphones and tablets and its standardized charge connector, today we can use the same charger for multiple electronic devices and it would have been nice to Jetbeam had implemented a microUSB port instead of the proprietary connector for charging. The SRA40 lacks any type of block-out, favoring accidental switching-on. Unscrewing the tailcap only interrupts the circuit when it is almost out (because the body of the torch electrically isolated), so this trick is not feasible with the SRA40. When using a digital button, the flashlight is never completely off, but goes to a standby mode which still consumes power, however after my measurements the parasitic consumption is totally negligible ( 0.09mA average = 1850 days = just over 5 years to exhaust a pack of 2000mAh NiMH AA ’s ) .
What also strikes me is the lack of a holster for a Premium flashlight, especially after knowing the final price of the SRA40. Mode sequence operates in a reverse order : High - > Medium -> Low. Although this not imply any serious problem, I consider more natural the reverse order.
I also think Jetbeam has sinned when give this flashlight a sequence of low modes , implementing two very usable intensities embedded in the sequence of timed stepdowns that the High mode makes along its continued use, the famous ” stepdown ” controlled by time. I think that would have been a success to have created user instant access to these intensities ( 640 and 435LM respectively) to provide a broader range of possibilities. In addition to this measure Jetbeam could have been removed (at least) the second stepdown, in my opinion totally unnecessary.
Finally, I miss a lower intensity; let’s say ~ 3LM, with a runtime of several days.

Positives: Overall, Jetbeam has achieved a solid and compact piece, which offers excellent performance and even incorporating a charging system in its “guts” just over the size of the precursor segment, EA4. In fact, barring the length that the three battlements and the supplement to the threaded punch / tripod, SRA40 has exactly the same length as the Nitecore EA4. The use of a double electronic switch on the head gives the SRA40 easier handling, without sacrificing some interesting features like the status monitor LEDs. Other positive note can be good ergonomics, since the small difference in diameter between the center and the head, equipped with cooling fins, make it much more natural to keep the flashlight in hand with a reference always at touch. Although personally never would install a punch in a flashlight of this type since this will kill the tailstand completely, the threaded hole is extremely useful for mounting flashlight on a tripod, making it a portable work lamp .
The integrated charger also provides a function that should not be neglected. As fans may we all have reliable external chargers and multiple sets of spare batteries, but putting ourselves in the shoes of someone who just needs a flashlight to work, I think it is an interesting factor to consider as it will allow us to have the flashlight always ready to walk without placing and removing batteries.
Its performance, stepdowns aside, is really impressive, coming very close to the 1000 ANSI LM, something that little few flashlights with a single XM-L can achieve , much less with simple AA batteries.

Please forgive my poor engrish! :weary:

awesome review,

thanks so much for the hard work!!

Thanks, fast kreisl!

your engrish post was faster!!


Awesome review, one of the best I’ve ever seen.

Thanks a lot! :slight_smile:

Thanks ryansoh3 :smiley:

Orsm review. Thanks. looks like another really nice AA light.

Great review thanks !

One question, you say “The battery arrangement is 2S2P” ?

So are you saying the XML LED is running from as battery supply of 2.4V ? If so Jetbeam have designed and made a very good boost driver.

Excellent review!

High first? Ugh… why is everyone doing that lately?
And a proprietary charger? :frowning:

If it had a Micro-USB connector, and was setup as Low-Med-High; even better would be if they included a lower-low (like the PA-40, Moonlight-Low-Med-High which they got perfect), then it would have been an instant sale. Otherwise, I’ll have to pass.

Too bad noone makes a light with a toggle switch inside the head, where you can switch between Low>High or High>Low. I’m sure that would add a few dollars onto manufacturing though.

Another impeccable review, very thorough and very goodlooking pictures, thanks!

(I own the D40A which I find very good and was not at all budget, so I'll pass this one)

What, another giveaway? I’m in.

Oh, it’s a review, sorry. Great stuff Upz

Yep, the flashlight is powered by two cells in paralel, and two in series.
When I was measuring the standby current drain, I checked by “bypassing” one of the 2 cell group and putting the DMM in series in the other group. I was able to measure a 2.2A drain in High mode from on the the series, so I guess the full current for max output whit fresh eneloops is around 4.4A (2.2A from each series).
AFAIK, Nitecore EA4 has the same battery distribution, and similar buck driver performance.

Thanks for the comment!

Thank you guys! :beer:

Maybe this is an interesting idea.
Do you know Nextorch MyTorch series? MyTorch18650 has a recharge MiniUSB port, which also works for the customization of the light UI.
Just in case manufacturers reads this, what about implemeting a MicroUSB plug for the charging feature, that can also be used to customize (just like the MyTorch series) the user interface via a simple PC sowtware with your OWN mode sequence?

I mean, you kill two birds with one shot (spanish say, not sure if it has sense in english or nor, lol) if you put a “universal” phisical conector that also allows you to give customer the power to customize and fine tune the tool to his own needs or taste.

Nextorch get it right, interesting idea, but unfortunatelly the series are in the “soft” side, with very gentle max outputs.


2S2P will give a supply voltage to the driver of 2.4V. This is less than the Vf of the LED, therefore it must have a boost driver not a buck driver.

EA4 gives 4.8V (four *1.2V) from is batteries, so requires a buck driver.

Hope UPz doesn't mind if I jump in here but the batteries are in 4S1P not 2S2P (one-UPz for an AWESOME review!) ^_^

The saying is virtually the same in english.

I like the microusb charging idea, although as nicely as this light is built, I still wouldn't pay the higher price with the modes it has. Your microusb programming idea should take care of that.

Very extensive and well done review, thanks, UPz :)!

Thanks for confirming, very confused for a bit there.