Vastlite Bow SFT25R#

Specifications#

Brand/model Vastlite Bow SFT25R
LED Luminus SFT25R 6500K
Maximum lumens 1,800 lm
Maximum beam intensity 15,750 cd
Maximum throw 250 m
Battery 1*18350 Li-ion USB-C
Onboard charging No
Material Aluminium
Modes 4
Blinkies Strobe, SOS, Beacon
Reflector Smooth
Waterproof IP68
Review date August 2025

Introduction#

The Vastlite Bow SFT25R is a forward-clicky 18350-sized EDC torch with the popular throwy Luminus SFT25R emitter.

Shenzhen Vastlite Technology Co., LTD. was founded by Leo Wong and Easy Dang. They have years of experience in the flashlight industry. You may already be familiar with their work on the BLF GT and the FW3A.

I met Leo in Shenzhen. He is eager to collaborate with the flashlight enthusiast community and he recommended reaching out if we have any designs that we would like to see come to life.

Here are some Vastlite torches that I have reviewed:

flashlightgo.com kindly provided this torch for review. I have not been paid for this review nor have I held back my opinions of this torch.

Packaging#

The Vastlite Bow SFT25R comes in a white box with VASTLITE on the top.

Vastlite Bow SFT25R packaging Vastlite Bow SFT25R packaging

The following was included in the box:

  • Vastlite Bow SFT25R.
  • Vastlite 18350 3.7V Li-ion 1100mAh USB-C cell.
  • Two spare o-rings.
  • User manual.

Vastlite Bow SFT25R packaging Vastlite Bow SFT25R packaging

Vastlite Bow SFT25R accessories

User Manual#

Vastlite Bow SFT25R user-manual

Torch in use#

The Vastlite Bow SFT25R feels smooth and comfortable to hold.

Vastlite Bow SFT25R in-use-2 Vastlite Bow SFT25R in-use-1

The forward-clicky tail switch is slightly shorter than the end of the torch.

Vastlite Bow SFT25R in-use-3

A two-way pocket clip is held in place by the tail cap.

Vastlite Bow SFT25R closeup-pocket-clip

The torch can tailstand.

Build quality#

The Vastlite Bow SFT25R has a matte light blue (grey) anodised finish. It is also available in MAO.

Vastlite Bow SFT25R front Vastlite Bow SFT25R left

Vastlite Bow SFT25R back Vastlite Bow SFT25R right

There is a little bit of knurling on the head and the tail to provide grip.

Vastlite Bow SFT25R side

There is protective film on the lens to remove.

Vastlite Bow SFT25R closeup-protective-film

There are six 2.3x2.05x9mm slots around the head for tritium vials or glow sticks to be installed.

Vastlite Bow SFT25R slots

The threads are anodised and they turn smoothly.

Vastlite Bow SFT25R threads

The tail switch gives a satisfying click. The spring under the button feels firm.

Vastlite Bow SFT25R button

There is a green glow-in-the-dark o-ring in the tail.

Vastlite Bow SFT25R closeup-rear

The retaining ring on the driver and the long tube mean that only certain protected button top 18350 cells are long enough to work.

Vastlite Bow SFT25R driver Vastlite Bow SFT25R tail-spring

LED, bezel, lens, reflector and beam#

The torch has a Luminus SFT25R emitter and a smooth reflector.

Vastlite Bow SFT25R closeup-emitter Vastlite Bow SFT25R closeup-bezel

CCT, CRI, and duv#

I have taken Correlated Colour Temperature (CCT) and Colour Rendering Index (CRI, RA of R1-R8) measurements with the torch positioned one metre away from an Opple Light Master Pro III (G3).

The CCT is around 6300K, the CRI is around 68 and the Delta u, v is positive (green) on Low and closer to pure white on High.

The bream produced has a white hotspot and some spill. There are a lot of ring artefacts in the spill when viewed on a white wall but they are not noticeable in real world use outside.

Mode CCT (K) CRI (Ra) x y Duv
Low 5936 66.5 0.3226 0.3454 0.0067
Med 6165 67.6 0.3183 0.3371 0.0046
High 6388 68.6 0.3147 0.3301 0.0028
Turbo 6808 70.1 0.3090 0.3185 -0.0004

Calculate Duv from CIE 1931 xy coordinates

Dimensions and size comparison#

Dimensions#

I took the following measurements using a digital caliper.

Measurement Unit (mm)
Length 92.00
Head diameter 23.50
Tail diameter 22.00
Tritium slot 2.3 * 2.05 * 9

Weight#

I took the following measurements using a digital scale.

Weight Unit (g)
Torch 49.87
Battery 25.89
Torch with battery 75.76

Size comparison with its competition#

From left to right: Vastlite Bow SFT25R, NLIGHTD E1 Copper, NLIGHTD L3 SFT25R Copper, Manker MC13 II SE, Olight Warrior Nano

Vastlite Bow SFT25R, NLIGHTD E1 Copper, NLIGHTD L3 SFT25R Copper, Manker MC13 II SE, Olight Warrior Nano

From left to right: Vastlite Bow SFT25R, NLIGHTD E1 Copper, NLIGHTD L3 SFT25R Copper, Manker MC13 II SE, Olight Warrior Nano

Vastlite Bow SFT25R, NLIGHTD E1 Copper, NLIGHTD L3 SFT25R Copper, Manker MC13 II SE, Olight Warrior Nano

User interface#

The Vastlite Bow SFT25R has a forward-clicky tail switch.

There are four main modes: Low, Med, High and Turbo.

There are three blinky modes: Strobe, SOS and Beacon.

State Action Result
Off Half press Momentary on (mode memory)
Off Half press within 3 seconds Cycle (Low, Med, High, Turbo)
Off Click On (mode memory)
Off Half press 5 times and click Strobe
Strobe Click off and click on SOS
SOS Click off and click on Beacon
Beacon Click off and click on On (mode memory)
On Click Off

Mode memory#

There is mode memory.

The torch will memorise the last used mode when the light is off for 3 seconds.

Strobe, SOS and Beacon are not memorised.

Strobe#

Strobe has a constant frequency.

Strobe, SOS, Beacon

Vastlite Bow SFT25R strobe Vastlite Bow SFT25R sos Vastlite Bow SFT25R beacon

I measured Strobe, SOS and Beacon with a Zoyi ZT-701 oscilloscope.

Low voltage protection#

There is low voltage protection. The light turns off around 2.7V.

I tested low voltage protection by connecting the driver of the torch to a bench power supply and then by lowering the voltage from 4.2V to 0V.

Mode LVP? Cut-off
Low Yes 2.77V
Med Yes 2.77V
High Yes 2.66V
Turbo Yes 2.62V

Pulse Width Modulation#

I did not notice any visible PWM (flickering).

I measured the PWM of the light with a Zoyi ZT-701 oscilloscope.

Low, Med, High, Turbo

Vastlite Bow SFT25R PWM Vastlite Bow SFT25R PWM Vastlite Bow SFT25R PWM Vastlite Bow SFT25R PWM

What I like about the UI#

  • Simple to use.
  • The spacing is good.

What could be improved#

  • Strobe could be easier to access. 2 fast half presses and a 3rd click would be nice.

Batteries and charging#

Battery#

A button top Vastlite 18350 3.7V Li-ion 1100mAh cell with USB-C charging was included inside the torch. It arrived with a voltage of 3.92V.

Vastlite Bow SFT25R battery-1 Vastlite Bow SFT25R battery-2

The cell was isolated with a piece of plastic to prevent accidentally turning the torch on.

Vastlite Bow SFT25R insulating-film

I tried the following cells:

Cell Top Compatible? Comment
KeepPower IMR18350 3.7V Li-ion 1200mAh Button Yes
Manker 18350 3.7V Li-ion 1100mAh USB-C Button Yes
Olight ORB-183C11 3.7V Li-ion 1100mAh Button Yes
Sofirn 18350 3.7V Li-ion 1100mAh Button Yes It works but the torch may turn off when rattled.
Vapcell M11 V2 18350 3.7V Li-ion 1100mAh (yellow) Flat No Too short and the retaining ring blocks the top.
Vastlite 18350 3.7V Li-ion 1100mAh USB-C Button Yes
Wuben ABJ1100C 18350 3.7V Li-ion 1100mAh Button Yes

Flat top cells do not appear to work.

Charging#

Power supply: PinePower Desktop USB-C
USB Meter: ChargerLAB Power-Z KM003C
Room temperature: 15 C

Vastlite Bow SFT25R charging profile

The battery took 1 hour 15 minutes to charge from 2.88V to 4.14V at a rate of 5V/1.2A.

The indicator light in the battery was red while charging and it became green when finished.

Vastlite Bow SFT25R charging-red Vastlite Bow SFT25R charging-green

Power supply compatibility#

I tried the following power supplies with the battery:

Power supply USB Type Protocol Does it charge?
Apple 61W Power Adapter USB-C PD Yes
Google Pixel Power Adapter USB-C PD Yes
PinePower Desktop USB-C PD Yes
PinePower Desktop USB-A QC Yes
PinePower Desktop USB-A Yes

USB-C to USB-C charging works.

Performance#

Specifications from the user manual:

Low Med High Turbo Strobe
Output (lumens) 25 300 650 1,800 1,000
Runtime 30h 1h 25min 1h 3min + 47min
Beam Distance (metres) 250
Beam Intensity (cd) 15,750

I tested the light using the included Vastlite 18350 3.7V Li-ion 1100mAh cell.

Lumen measurements#

I used a bench power supply to measure the current at turn on.

Mode Amps at start Specs Lumens @turn on Lumens @30 sec Lumens @10 min
Low 0.05 A 25 21 21 19
Med 0.42 A 300 243 238 236
High 1.13 A 650 549 537 519
Turbo 5.95 A 1,800 1,275 1,119 515

Runtime graphs#

I used my own DIY lumen tube with a TSL2591 sensor and forked bmengineer’s project RuTiTe to record runtimes.

Note: Lumen measurements may be off by 10% with my DIY lumen tube.

The room temperature was approximately 15 C.

Vastlite Bow SFT25R runtime graph

Vastlite Bow SFT25R first 2 hours runtime graph

Vastlite Bow SFT25R first 10 minutes runtime graph

Runtime#

Here is a summary of the runtime results:

Mode User manual Runtime Turn off Final voltage
Turbo 3min + 47min 48min 41s 52min 48s 2.806
High 1h 57min 24s 57min 24s 2.960
Med 1h 25min 2h 31min 22s 2h 31min 22s 3.096
Low 30h 26h 11min 32s 26h 11min 32s 2.853

“Runtime” is the time until the output reduces to 10% of the output at 30 seconds (as per the ANSI/PLATO FL1 2019 Standard).

“Turn off” is the time until my DIY lumen tube no longer detects more than one lumen.

“+” indicates that the light remained on after recording had stopped.

The runtime results for Turbo and High were pretty close to what Vastlite claim. Medium was better than expected while Low fell short by a few hours.

The output is well regulated.

Throw#

I took lux measurements with a UNI-T UT383BT at 30 seconds. Turbo was measured at five metres.

Mode Specs (cd) Specs (m) Candela measured (cd) Distance (m)
Turbo 15,750 250 27,900 334

The beam distance is better than expected.

Beamshots#

I went to a local park and I aimed the torch at a tree 70 metres away while using Turbo.

Beamshots were taken using a Sony RX100M2 using 3.2", f3.2, ISO 800, 5000K WB.

Vastlite Bow SFT25R (Turbo)#

Vastlite Bow SFT25R Turbo beamshot

Manker MC13 II SE (Turbo) 18350#

Manker MC13 II SE 18350 Turbo beamshot

NLIGHTD E1 14500 (Turbo)#

NLIGHTD E1 14500 Turbo beamshot

Manker E05 II (High)#

Manker E05 II High beamshot

Olight Warrior Nano (Turbo)#

Olight Warrior Nano Turbo beamshot

Thermal Images#

I used a Zoyi ZT-R01 IR Thermography Multimeter to take thermal images of the torch on a silicone mat while using Turbo.

Room temperature: 12 C

Time (mm:ss) Max Temperature
00:00 16.8 C
01:00 37.4 C
02:00 47.1 C
03:00 48.7 C
04:00 46.0 C
05:00 44.4 C

The temperature peaked at around 49 C within the first 5 minutes.

Vastlite Bow SFT25R Thermal Image Vastlite Bow SFT25R Thermal Image

Vastlite Bow SFT25R Thermal Image Vastlite Bow SFT25R Thermal Image

Vastlite Bow SFT25R Thermal Image Vastlite Bow SFT25R Thermal Image

Conclusion#

The Vastlite Bow SFT25R is a nice little pocket thrower!

The design looks and feels elegant.

Vastlite have achieved a better beam distance than expected by combining a Luminus SFT25R with a smooth reflector. I measured over 330 metres on Turbo after 30 seconds.

The lumen output was lower than expected. I measured around 1,100 lumens on Turbo after 30 seconds while Vastlite expected it to be 1,800 lumens.

A high drain button top 18350 cell might achieve better results. It would be nice if the retaining ring could be thinner so that flat top cells fit, and if longer springs were used for a tighter fit for short cells.

The driver is good. Output is well regulated. Low voltage protection is built-in.

Overall, I can recommend the Vastlite Bow SFT25R if you are looking for a compact pocket thrower with an elegant design.

Pros:#

  • Good build quality.
  • Good runtime results.
  • Output is well regulated.
  • Beam distance is better than expected.
  • Simple user interface.
  • Battery has built-in USB-C charging.
  • Secure two-way pocket clip.

Cons:#

  • Lumen output is lower than expected.

Price#

The Vastlite Bow SFT25R is US$43.20 from flashlightgo.com after discount.

It is also available with a MAO finish.

Product page#

Promo code: TIM

Vastlite Bow SFT25R at flashlightgo.com (affiliate link)

I may earn a commission if you use an affiliate link or a promo code. This will help fund future torch reviews and tutorials.