Vastlite Bow⌗

Specifications
Introduction
Torch in use
Build quality
LED, bezel, lens, reflector and beam
Size and comparison
User interface
Batteries and charging
Performance
Beamshots
Conclusion
Price
Product page

Specifications⌗

Brand/model	Vastlite Bow
LEP	CT1-Mini
Maximum lumens	280 lm
Maximum beam intensity	140,650 cd
Maximum throw	750 m
Battery	1*18350 Li-ion
Onboard charging	No
Material	Titanium
Modes	2
Blinkies	Strobe
Waterproof	IPX8
Review date	September 2024

Introduction⌗

The Vastlite Bow is a small 18350-sized torch with an 8.4W transmission-type LEP module and a forward clicky tail switch.

It is available in raw and stonewashed titanium.

Shenzhen Vastlite Technology Co., LTD. is a new flashlight company 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 last year in Shenzhen. He is eager to continue 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.

Nealgadgets 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⌗

I received an early sample of the Vastlite Bow before the packaging and user manual were created.

The Vastlite Bow came wrapped in bubble wrap.

Torch in use⌗

The Vastlite Bow feels comfortable in my hand.

There is forward clicky tail switch to provide access to Low, High and Strobe modes.

The torch can tail stand.

There is no lanyard hole but you could attach a lanyard to the pocket clip.

Build quality⌗

The Vastlite Bow is made of titanium. This particular version has a raw finish.

The 8.4W LEP module is housed inside a copper pill.

Knurling near the tail and near the head provide additional grip.

There are six 3x8mm slots around the head for tritium vials or glow sticks to be installed. 2x7.5mm may be a good size for the glow sticks.

The depth of each slot is around 2mm while the width is 3mm and the length is between 8.14mm and 8.5mm.

This is what 3x6.8mm glow sticks look like (not included):

The threads turn relatively smoothly for titanium.

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

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

A two-way pocket clip is held in place by the tail cap and it fits snugly on my pocket. I tried unsuccessfully to unscrew the tail cap with my hand.

The notch on the driver and the spring at the tail allow both button top and flat top 18350 cells to fit.

A brass retaining ring on the driver blocks recessed top cells from working.

The torch appears to have reverse polarity protection. I put a flat top 18350 cell in backwards and I tried to turn the torch on. The torch did not turn on. The torch continued to work properly after I put the cell in the correct way.

Warning: I do not recommend attempting to put a cell in backwards at home because the cell could short and explode. A cell with a misaligned or damaged wrap might make contact with the retaining ring near the head or the side of the tube and create a short.

The driver has an FMD (Fremont Micro Devices) MCU.

LED, bezel, lens, reflector and beam⌗

The Vastlite Bow has an 8.4W transmission-type LEP module. It is the CT1-Mini LEP module from Blue Lake. You can get LEP modules here.

There is a glass lens sitting in front of a green glow-in-the-dark o-ring. This is sitting on another lens to focus the beam. Behind that is copper pill containing the LEP module.

I have not been able to remove the LEP module with snap ring pliers. It would be nice to be able to disassemble it so that I can customise it further (e.g. add different coloured glow rings).

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 five metres away from an Opple Light Master Pro III (G3).

The CCT is 7000K to 9000K, the CRI is around 67 and the Delta u, v is positive (green) on Low and closer to pure white on High.

The beam produced is narrow and it has a practical hot spot for EDC use.

Mode	CCT (K)	CRI (Ra)	x	y	Duv
Low	7000	63.8	0.3031	0.3329	0.0101
High	9286	70.2	0.2840	0.2937	0.0008

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	89.47
Head diameter	23.63
Tail diameter	22.49
Button diameter	9.8
Tritium slot	3 * 2 * 8.18

Weight⌗

I took the following measurements using a digital scale.

Weight	Unit (g)
Vastlite Bow	100.91

Size comparison with its competition⌗

From left to right: Vastlite Bow, NLIGHTD L2, Lumintop Petal

User interface⌗

The Vastlite Bow has a forward-clicky tail switch.

There are two main modes: Low and High. And one blinky mode: Strobe.

State	Action	Result
Off	Half press	Momentary on (mode memory)
Off	Half press within 1 second	Cycle (Low, High)
Off	Double press quickly	Strobe
Off	Click	On (mode memory)
On	Click	Off

Mode memory⌗

There is mode memory.

The torch will memorise the last used mode (Low or High) after leaving the torch turned off for more than 3 seconds.

Strobe is not memorised.

Strobe⌗

Strobe has a constant frequency.

I measured Strobe with a Zoyi ZT-703S oscilloscope using High Speed mode.

Low voltage protection⌗

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

There is a low voltage warning. The light blinks four times when the voltage gets low. The warning occurs around 3V, before the cut-off is reached.

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	Current
Low	Yes	2.78V	0.001A
High	Yes	2.54V	0.000A

I was able to turn the light back on when the voltage was below 2.5V but it blinked four times after five seconds and then it turned off again.

I wanted to how low the voltage could get while still providing enough power for the LEP module to work so I kept turning the light back on while turning the voltage down. The LEP module kept working down to 1.91V.

Pulse Width Modulation⌗

I did not notice any visible PWM (flickering).

I measured the PWM of the light with a Zoyi ZT-703S oscilloscope.

Low, High

What I like about the UI⌗

I like the forward-clicky tail switch.

What could be improved⌗

It would be nice if the timing could be adjusted slightly so that I do not accidentally enter Strobe. If press the tail switch quickly while trying to change between Low and High, it might enter Strobe.
A Lockout mode would be useful but I am not sure how this could be implemented. I would recommend placing a plastic circle near the head of the battery if carrying the torch in a backpack so that the tail switch is not accidentally clicked.

Batteries and charging⌗

Battery⌗

The Vastlite Bow accepts most button top or flat top 18350 3.6V/3.7V Li-ion cells.

I found that unprotected, protected or protected cells with built-in USB-C charging work. However, 18350 cells with a slightly recessed top might not fit because the outer part of the cell will press against the brass retaining ring for the driver and the positive end of the cell will not make contact with the little notch on the driver.

I tried the following cells:

Cell	Top	Compatible?	Comment
Vapcell M11 18350 3.7V Li-ion 1100mAh (purple)	Flat	Yes
Vapcell F14 18350 3.7V Li-ion 1400mAh (green)	Recessed	No	Brass ring blocked the top from touching.
KeepPower IMR18350 3.7V Li-ion 1200mAh	Button	Yes
Manker 18350 3.7V Li-ion 1100mAh USB-C	Button	Yes	It is a tight fit. The cell is long.
Olight ORB-183C11 3.7V Li-ion 1100mAh	Button	Yes
Wuben ABJ1100C 18350 3.7V Li-ion 1100mAh	Button	Yes

Charging⌗

There is no built-in charging.

Performance⌗

Specifications from the user manual:

	Low	High	Strobe
Output (lumens)	100	300	120
Runtime	1h 30min	90s + 1h 30min
Beam Distance (metres)		750
Beam Intensity (cd)		140,650

I tested the light using an old high drain flat top Vapcell M11 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	0.629 A	50	77	73	69
High	2.545 A	280	316	290	64

Standby drain⌗

There is no standby drain. This torch has a forward-clicky tailswitch.

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.

Runtime⌗

Here is a summary of the runtime results:

Mode	User manual	Runtime	Turn off	Final voltage
High	90s + 1h 30min	1h 15min 40s	1h 15min 40s	3.05
Low	1h 30min	1h 19min 44s	1h 19min 44s	2.82

“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 are close to what Vastlite claim. I used an old high drain Vapcell M11 18350 (purple) cell so that may have impacted the runtime slightly.

High stepped down to a Low output level after 2 minutes. It would be even better if it had a Medium mode or if High stepped down to a higher output level than Low. That said, you can simply reactivate High after it steps down by turning the light off and on again.

The tube is comfortable to hold but the top of the head gets warm on High. The surface temperature of the head reached 20 C at 30 seconds, 27 C at 2 minutes, and 50 C at 8 minutes when I re-activated High after the initial step down.

Throw⌗

I took lux measurements with a UNI-T UT383BT at 30 seconds. Low and High were measured at ten metres.

Mode	Specs (cd)	Specs (m)	Candela measured (cd)	Distance (m)
Low			42,700	413
High	140,650	750	148,000	769

Beamshots⌗

I went to a local park and I aimed the torch at a tree 100 metres away while using High.

Beamshots were taken using a Sony RX100M2 using 1.3", f3.2, ISO 800, 5000K WB.

Vastlite Bow (High)⌗

NLIGHTD L2 (High)⌗

Lumintop Petal (LEP High)⌗

Here are more beamshots of the Vastlite Bow:

Conclusion⌗

The Vastlite Bow is a fun sized LEP torch for enthusiasts!

Six slots around the head allow you to add your own tritium vials or glow sticks.

I am liking the raw titanium finish.

The beam distance and lumen output are slightly better than expected.

The output is very stable. I do wish that it had a Medium mode but the Low mode is practical and it is fun to re-activate High.

An aluminium option would be nice too.

This is a great torch for Vastlite to launch their brand with.

I highly recommend the Vastlite Bow.

Pros:⌗

Small size.
It accepts a wide range of 18350 3.7V Li-ion cells.
Good beam distance.
Good build quality.
Simple user interface.
Output is well regulated.

Cons:⌗

High drops off after 2 minutes to a Low output level.

Price⌗

The Vastlite Bow is US$127.95 from nealsgadgets.com

Product page⌗

Promo code: TimMcAU
Promo code: TIMMC
Promo code: BowNN for 25% off.

Vastlite Bow at nealsgadgets.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.

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