Speras U2T

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Speras U2T Specifications & measurements

Brand & Model	Speras U2T
Flashlight category	Multipurpose/Bicycle
LED	3*Luminus SST40
Max. output	5,000 lumens
Max. beam distance	340 meters
Max. beam intensity	28,875 cd
Battery config.	2*18650 battery pack, built-in
Onboard charging	USB-C
Main modes	5
Blinkies	Strobe, SOS
Waterproof	IP68
Review publication date	August 2024

Another Speras light on deck, and this one’s special. The flashlight market is what business analysts and marketing strategists call a vertical one, with products designed and adapted for a specific use-case and consumer demographic. Basically design and market a product that lights stuff up. For decades, a flashlight was a tube-shaped, cylindrical device, and that was that. If it ain't broke, don’t fix it, right? However, in recent years, we’ve started to see variations on that theme, with light designs taking on a more ‘angular’ form factor. Parallelogram, rectangle, what have you.

I’ve reviewed the Nitecore TM12K, NEXTORCH TA31, Streamlight Stinger 2020, Fenix E03R v2 to name a few, and more manufacturers are throwing their ‘non-round’ flashlights into the mix. Now Speras has one…the U2/U2T. This one’s fresh out of Kickstarter, a project introduced in December 2023 and quickly gained a lot of ground. Speras put a lot of planning and bran cells into this one, and I think it might just be the most versatile portable illumination tool available currently with lots of mounting and switching options. I dig multipurpose flashlights, so let’s dig in.

What's in the package

The Speras U2T comes in a nice, retailable package (even though I’ve never seen these for sale in stores here), so there’s graphics and feature blurbs everywhere, front and back. Here’s what’s inside:

• Speras U2 flashlight
• Instruction guide
• O-rings
• Lanyard
• USB C charging cable
• BM2 bicycle handlebar mount (optional)
• WK01 wireless remote (optional)

This is a ready to run kit, and my tester included the optional WK01 wireless remote (Speras sent after receiving the tester) and BM2 bike mount. This ups the versatility factor a lot since now the U2T can go on bike duty, or clip to a mount, mast, tripod, etc and be controlled remotely with the remote. Neat! The bike mount also included a 1.5 mm allen wrench and 4 hex head screws for securing the quick-release mount. I appreciated the extra screw when you invariably lose one. You get lots of output out of the box, but it would be wise to fully charge the battery before use for maximum output.

Speras’ goals with the U2T were clear: To make a true sport utility flashlight, a multi-role lighting tool that can wear a lot of hats and do a lot of things. The U2T is designed to be as compact as possible while maintaining high output. First off, it’s not round, but rectangular. The design is identical in execution to the Nitecore TM12K and I actually like this form factor. It fits well in the palm, and the host is sized right to fit most hands. I have big hands, and the U2T felt like a smaller light than it is, even smaller than the Nitecore TM12K. While the shape took some getting used to handling-wise, after a while, it feels nice and natural in the hand, and I found the edge-mounted e-switch and rear clicky easy to reach in all grip positions. There’s no knurling per-se, but Speras machined in grooves and ridges where they felt they were needed. 

For carry and retention, the U2T can be pocket carried, but even though Speras did a good job with the form factor, it’s a bit too big and heavy for regular EDC, but would fit fine in cargo pockets or clipped to a pack, belt, or turnout with the detachable dial-position clip. You get bezel up or down retention, but you need a 1.5 mm hex allen wrench or hex bit to remove the 2 screws securing the clip (included if you get the optional BM2 mount kit).

The BM2 mount is optional and adds lots of versatility. The mount has a quick-release shoe that’s secured to the opposite side of the light with 3 included screws. Once the mount is installed, the light can be slid onto the BM2 mount. The mount is on a swivel that can pivot left or right about 45 degrees, and is secured to bike handlebars using a cinch strap which works sort of like a hose clamp. Rotate the plastic nut clockwise to tighten the strap, reverse it to loosen. The mount has a soft rubber pad on the gripping surface for traction to help hold it steady and prevent damage to the hadelbar’s finish. 

For switching, you have options. There’s a single e-switich on one edge. This ‘T’ version adds a rear tail forward clicky for momentary use. It’s a multidirectional switch that can be pressed on the sides or in the middle. Pressing the sides activates instant strobe, and half-press or fully clicking activates either momentary or constant-in Turbo.

Speras makes a wired remote, but the ace in the hole for the U2T is the wireless remote control.

The kit included the Speras WK01 wireless remote and USB C receiver/antenna. It looks like a wireless key fob with 3 buttons labeled A, B, C. More on that in the UI overview. The remote can control the U2T from up to 15 meters away. Obviously, a wireless remote adds an absolute ton of versatility for hands-free operation. I found it very handy for turning the light on as an area light from a distance to light up a dark room, or lighting up a tent without reaching for the light (if I had a dollar for every time I wish I had that feature I could buy a U2T).

As a bike light or worklight, that would also be great since you wouldn’t have to take your hands off your work/bike to change lighting modes or turn the light on/off. Way to go Speras! Opposite the switch is the USB C charge interface. It’s sealed with a rubber cover that fits flush with the host and makes a tight, snag-free seal.

Build quality for the U2T, like all my Speras lights, is great. Nice and tidy on the machining, fit, and finish. I didn’t notice any issues with ill-fitting parts or other anomalies. Overall, this is a very well-built light. It’s competitively priced for what it is. With optional bike mount, wireless remote, and gradient color, it’s coming in around $80 to $110 US, which isn’t at all unreasonable. The light is milled from the typical 6061-T6 aluminum alloy. It’s blemish-free and there’s no sharp edges anywhere on this light, which I expect for a holster-ready light.

The finish comes in either solid black, or a green/black gradient finish. It’s type III HA hard anodizing, and it’s also well done. It’s a semi-gloss finish and not super-grippy, but feels high quality. The light is sealed up tight, and Speras gives it an IP66 rating, good for temporary immersion and the worst rainstorms Mother Nature can muster. 

For the warranty, from Speras.com: 1. Within 30 days, free replacement. SPERAS will provide 30 days free replacement service of purchase for any manufacturing defects if problems come into being in normal use; We will replace it with the same model. If the model has been discontinued, customers will receive a product with similar or improved model. 2. Within Warranty time: Usually we provide 5 years warranty, some may provide lifetime limited warranty( for example E1). Within the warranty time, any defects please contact local dealer or distributor for warranty support. We will repair or we replace a new product for you according the defects. 3. The free warranty does not cover any damages or failure caused by: Normal wear, rough operation, battery leakage

The LED choice for the Speras U2T is on point in the Luminus SST40. While everyone seems to gravitate to the SFT-40-W these days, and rightfully so, the elder statesman SST40 is still entirely relevant even in 2024. While it’s not fancy with high CRI or pleasant tints, it has a low vF, is efficient at moderate power outputs, and can get really bright if driven hard.

The U2T uses 3 of these on a single DTP copper MCPCB for maximum thermal efficiency. They sit in a 3 cup SMO reflector with the 3 LEDs in a row, which should help even out the beam and give a nice light dispersion. It’s capped by an AR coated mineral glass lens. There’s minimal bezel protecting the lens though. The beam is really floody, and there is a bit of a hotspot so you get some beam distance that’s usable out to 200 meters. Overall, an excellent general purpose beam, and one that can be useful on a bike. However, while the U2T beam is adapted slightly for bike use, a dedicated bike light would probably be better since the U2T does have glare up top that could be distracting to motorists, other cyclists, or pedestrians. 

Spectral measurements: 

I used the Opple Lightmaster Pro to measure the flashlight at 1 meter from the sensor. 

Mode:	CCT:	CRI Ra:	duv
Turbo	5455K	60.2	0.0132

The cooler CCTs of SST40 are known to shift green and +duv, so no surprise here! In person it looks better than the reading suggests, but on Low mode, it’s noticeably green, but not as bad as a CW SST20 or LH351D.

Dimensions: 

Speras U2T	Millimeters	Inches
Length	107 mm	4.2 in
Width	43 mm	1.7 in
Thickness	24 mm	0.94 in

Dimensions are rounded to the nearest millimeter and the nearest tenth of an Inch.

Weight: 

Speras U2T	Weight in grams	Weight in oz
With battery	227 g	8 oz
With BM2 mount	250 g	8.8 oz

Weight is rounded to the nearest gram and tenth of an Oz.

Flashlight size comparison with its competition:

Group 1 left to right: NEXTORCH TA31, Speras U2T, Nitecore TM12K, Streamlight Stinger 2020

Group 2 left to right: Nitecore TM12K, Speras U2T

Speras lights usually have fully regulated drivers, either boost or buck drivers. The U2T probably has a buck driver for fully regulated output. These are superior to the cheaper FET or linear drivers since output isn’t dependent on battery voltage until LVP kicks in, so you get constant output that doesn’t drop as the battery discharges. 

The UI is commensurate for a light like this, a dead simple 5-mode affair with nicely spaced modes plus two blinkies.

Available modes: 

• Eco, Low, Medium, High, Turbo

Available blinky modes:

• Strobe, SOS

From OFF:

• Press and hold side switch: Turns on in last used mode
• Fully click rear switch: Turns on in Turbo
• Half-press rear switch: Momentary Turbo
• Double click side switch: Strobe. Double-clicking again switches to Beacon, and double clicking again activates SOS
• Push the sides of the tail switch: Activates strobe

From ON:

• Press and hold side switch: Turns off
• Click side switch: Changes modes
• Tap rear switch: Momentary Turbo
• Fully click rear switch: Turbo
• Double click side switch: Strobe
• To activate High 2, double click in Turbo
• Push the sides of the tail switch: After 0.3 seconds, Strobe is activated

Mode memory:

• Remembers last brightness level including Turbo. Blinkies are not memorized 

Shortcuts:

• To Turbo: Half press or click rear switch
• To Strobe: Double click to activate Strobe. To cycle through SOS and Beacon, double click again for each mode

Low voltage warning/protection:

• The light will drop to a very low level when the batteries reach a certain low voltage (not specified in the manual)

Strobe/blinkies

• Strobe, Beacon, SOS
• Double click side switch from off. Double-clicking again switches to Beacon, and double clicking again activates SOS

Lock-out mode: 

• Electronic lockout. From off, press and hold the side switch for 2+ seconds. The light will blink once and the light is locked. If the switches are pressed, the side switch LED lights up orange.
• To unlock, triple click. The light flashes twice to acknowledge.

PWM

• None visible

Additional/summary info on the UI: 

• For the remote switch, the three buttons labeled A, B, and C control different functions. After plugging the antenna into the USB C port, long press the A switch to turn the light on. Click again to turn off. The B and C switches are the same, funcion-wise.
• From on, clicking the B or C switch changes modes. Pressing and holding B or C activates momentary Strobe. From off, clicking B or C will activate momentary Strobe.

• I like this UI a lot. It doesn’t require a learning curve and incorporates well-spaced modes. Turbo isn’t a separate function and part of the main modes, which I happen to like, and Turbo and Strobe can be called up instantly with the rear clicky switch. While user-preference, and if square lights are your thing, I wouldn’t dissuade someone from using the U2T for duty or tactical applications since the rear switch affords instant access to ‘tactical’ modes.

The U2T contains two 18650 li-ion batteries inside the rectangular housing. These are in parallel, and the total capacity is 6400 mAh, so each cell is roughly 3200 mAh. Not surprisingly, these cells are integrated and cannot be removed (at least not destructively), so when they go flat, you either send the U2T to the recyclers in the sky, use it as a paperweight, or gift it to someone you don’t like.

The charging is USB type C, and Speras says it’s good up to 15 watts (5 volts 3 amps). It’s also a power bank, and can run off a C to C cable and charge your devices up to the same 15 watts.

Speras includes a USB OTG adapter (on the go) dongle which is a C to A adapter that accepts a USB A to C cable. It’s made of aluminum and has a tiny lanyard on it. I’d still consider this an emergency power supply since fully charging most modern mobile phones with a 4.2 Ah battery off the U2T would mostly drain the battery.

On the Hidance USB C tester I was seeing around 17 watts and on the Ruideng AT35 USB A tester I was getting around the same. Charging up some other flashlights and devices on the power bank I was getting between 8 to 13 watts. Speras says the battery should charge in about 2 hours, and after a runtime, my USB meter showed charge termination after 2 hours 3 minutes to add 5378 mAh. 

Charge type	Fits	No fit	Charge time
Flashlight with onboard USB-C	N/A	Everything	2h 3min

Lumen measurements

How Lumens are Measured: Understanding ANSI FL1 Standards

About Lumen measurements: The ANSI FL1 standards specify that output in lumens should be measured 30 seconds after turning on, as this is the standardized time for measuring brightness according to the industry standard. This is why we focus on this part in our measurements. The ANSI FL1 standards require an ambient temperature of 22 ± 3°C. We record the ambient the ambient temperature to identify potential reasons for any observed discrepancies.

Lumens are measured in my 50 cm integrating sphere with a Digi-Sense 20250-00 data logging luxmeter. The sphere has been calibrated with a Convoy S2+ measured to 260 Lumens and the figures are within 10% of actual. The sealed electrical path made measuring the current impossible.

Mode	Specified	Turn on	30 sec.	10 min.
Eco	12	12	12	-
Low	180	185	185	-
Medium	500	486	486	486
High	2000	2120	2074	615
Turbo	5000	4560 lm	4256 lm	684 lm

Ambient temperature during testing:

•  21 °C 

The outputs looks good and agree mostly with Spera’s advertised figures, albeit I’m a bit down from advertised on Turbo and Medium.

Battery Life: Runtime graphs

How Runtimes are Measured: Understanding ANSI FL1 Standards

About ANSI FL1 runtime standards: The runtime is measured until the light drops to 10% of its initial output (30 seconds after turning on). This does not mean that the flashlight is not usable anymore. The last column shows how long the light actually works till it shuts off. If there is a + symbol, it means that the test was stopped at that particular point, but the light was actually still running. This happens on certain occasions, with certain drivers, firmware, or batteries.

Lumens are measured in my 50 cm integrating sphere with a Digi-Sense 20250-00 data logging luxmeter. The sphere has been calibrated with a Convoy S2+ measured to 260 Lumens and the figures are within 10% of actual. I use a Digi-Sense 20250-92 data logging thermocouple for the temperature measurements. The probe is affixed to the head using kapton tape and uses the same 5 second sampling rate for logging.

I tested Medium, High and Turbo modes. The battery was allowed to fully charge before each test.

Mode	Specified	Runtime (ANSI FL1)	Time till shut off
Medium	6h 30min	7h	7h
High	4h 42min	5h 19min	5h 26min
Turbo	4h	4h 19min	4h 27min

I’m glad Speras put a regulated driver in the U2T. We see nicely regulated output across all of the (measured) runtimes here. While I hit the output specs for all modes except Turbo, these all look good. On High, you’re getting better than 1000 Lumens for over 2 minutes, and Turbo delivers better than 2000 Lumens for almost 60 seconds.

After 180 seconds though, High and Turbo are down to around 600 Lumens, where they camp until a step down to around 150 Lumens for a short time before shutting down. Medium gives around 500 Lumens for nearly 7 hours before stepping down to around 100 Lumens, then shutting down.

Temperatures were kept well in check, never exceeding 55 C, and the host was comfortable to hold even after prolonged Turbo use. The conservative thermal limit might be the reason for the unimpressive sustained output for a triple LED light, but I get the design limits heat sinking and thermal capacity. Turbo can be recalled (any mode really) after the first step down. For LVP, I didn’t notice any visual notifications, other than the blinking switch LED.

For the comparison testing, I grabbed some other triple or quad LED lights. You can see that the U2T holds its own on High, but falls behind the others in sustained output.

Peak beam intensity and beam distance measurements

About Peak beam intensity: Understanding ANSI FL1 Standard

About peak beam intensity: The calculated value of distance in meters at which the flashlight produces a light intensity of 0.25 lux. (0.25 lux is about the brightness of a full moon shining on an object). This means that the intensity has decreased so much, it becomes difficult to see darker objects, or objects that don't reflect light. The columns ‘Meters’ and ‘Yards’ use rounded numbers.

Beam distances are measured using a Uni-T UT383S luxmeter measured indoors at 5 meters. Measurements taken at 30 seconds. The light was recharged and allowed to cool between the High and Turbo tests.

Mode	Specified	Candela measured	Meters	Yards
Eco	66	50 cd	14	15
Low	1187	925 cd	61	67
Medium	3100	2675 cd	103	113
High	12,500	11,500 cd	214	234
Turbo	28,875 cd	25,425 cd	319	349
Turbo at turn-on	?	27,950 cd	334	365

Ambient temperature:

•  21 °C 

Turbo at ANSI is 319 meters, and this is pretty good beam distance, but down from advertised. Still, more than enough for most tasks.

Camera settings and distance: Photos taken with a Canon EOS R100 with Canon RF-S 18-45 mm STM lens. The camera is set to 0.3s, F5 ISO1600 and 5000K WB. The fence is 95 meters away.

Beamshots of the following flashlights compared:

• Speras U2T
• NEXTORCH TA31
• Astrolux EC03
• WildTrail WT3M
• Astrolux FT02S v2
• Acebeam E75 (with different camera settings)

Please note that the following beamshots are mainly intended to showcase the beam pattern and beam quality, rather than overall performance. These images are typically taken directly after activation, and in different seasons or weather conditions, and therefore do not fully represent its overall performance. In few cases the camera settings are even different and therefore not meant for performance comparisons. For accurate performance metrics, such as output, beam distance, and runtimes, you need to look at the performance section of this review.

Disclaimer: This flashlight was sent to us for review at no cost by Speras. We have not been paid to review, nor have we been holding back on problems or defects.

Get 10% off at Speras store with our unique coupon code: LUMEN

1lumen selects and reviews products personally. We may earn affiliate commissions through our links, which help support our testing.