Weltool W4 PRO

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Weltool W4 PRO specifications

Brand/model	Weltool W4 PRO
LEP	Mirror style LEP
Max. Lumens	568 lm
Max. Beam intensity / distance	2,882,000 cd
Battery config.	1*21700
Onboard charging	N/A
Modes	2
Blinkies	Strobe
Reflector	N/A
Waterproof	IP67
Review date	May 2022

Weltool kind of started the whole craze around LEP flashlights back in 2018 with the Weltool W3. It was one of the greatest steps forward in the world of flashlights when it comes to beam distance and beam intensity.

Instead of using an LED as its light source, an LEP uses a laser as its light source. A blue laser projects its light onto phosphor to turn the blue laser into a white beam. Then the beam gets focused using a convex lens. This type of flashlight can only used for long-distance objects. But I can already share a little secret: that won’t be for long, because Weltool is working on a different type of application where the beam get’s wider, more like the average LED beam.

But that review will come later.

So, how will the Weltool W4 PRO stack up against its older sibling the W4? Will it throw farther? Did Weltool really improve the W4? On paper it should, because the W4 had a claimed beam intensity of 1.7Mcd, and the W4 PRO 2.8Mcd… that’s a million candela more.

So, let’s find out.

Package quality.

When Weltool sent me the light, they were still working on the packaging, so I can’t show you any of that. They just shipped it in the W4 packaging. So this is likely going to be inside the packaging…

• The flashlight: Weltool W4 PRO
• Weltool 21700 battery with USB-C port
• USB-C charging cable for the battery
• Pocket clip attached
• Spare o-ring
• Manual

The original W4 has been around since 2020, so a successor was kind of due. And I’m glad they stuck with the W4 design because it looks and feels awesome.

The battery tube has the typical spiral knurling also seen on the W3 PRO and W4. However, the neck of the light, as well as the tailcap, has no knurling. The tailcap has some cut-outs that work as an anti-roll feature, but only on a flat surface. It’s too little to protect from rolling off a slightly inclined surface. The pocket clip would help more in that regard.

Talking about the pocket clip.

The clip came pre-attached and is removable. But since it’s such a large light, I’m not sure how many people would use it though. A holster would probably be a better idea, which wasn’t included in the box. Weltool sells a holster for the W4 PRO separately, as: Weltool FH6. It’s only $9 and probably worth the little extra if you like using holsters.

There’s only one switch, and that’s a forward clicky tail switch. And because of that, you can momentarily turn the light on by half-pressing (not fully clicking) the switch.

It has a clear clicky sound and can be pushed from about 45 degrees. The rubber boot feels a bit ’empty’ though like there is a lot of play without touching the actual switch.

These flashlights have a particular use case since their beam is so tight and reaches so far. Think about search and rescue, signaling over long distances, or simply using it as a beacon.

The build quality of all Weltool flashlights is top-notch.

While some manufacturers mainly focus on output, weltool pays great attention to build quality. Just like the W4, the W4 pro looks beautiful.

The body tube has particular Weltool knurling, with bare threads on 1 side, and anodized threads on the other. The bare threads are towards the head, and are protected from water ingress by a single o-ring.

The rear threads are lubed, screw smoothly, and protected by 2 o-rings for waterproofness

Weltool Warranty: from their website:

“Weltool warrants its products to be free of defects for a lifetime of use. We will repair any light device which is found to be defective under normal use.

​ From the date of sale (the serial number on the Lights body can show the date), the limited warranty for LED products is 5 years, and the warranty for LEP products is 2 years.

The above free warranty does not cover any damages or failure caused by:

• Problems caused by alteration, misuse, abuse, or unreasonable
• Battery leakage , improper operation or using poor quality battery
• The products do not purchase from Weltool directly or its authorized dealers or other illegal way
• Broken lens caused by external force
• Lamp, switch runs out of its lifespan
• rubber cap, O ring’s naturally aging
• normal wear and tea, imprinting, or color finishes
• Other problems caused by improper operation
• Discontinued products

The W4PRO is an LEP flashlight, not an LED flashlight, so the light source is based on a laser rather than an LED emitter. These types of lights have a higher beam intensity compare to LED flashlights.

The bezel is made of stainless steel which increases impact resistance, and according to the manual, the W4 PRO uses a tempered glass lens for extra protection.

The laser warning, that was present on the older W4, is absent on the W4 PRO, and originally said: Warning, Class 3B Laser Product. btw Laser flashlights are never meant to be used by children because the beam is so intense, that it could hurt people’s eyes.

Talking about the beam, the W4 PRO is using the traditional mirror type LEP module. This means that the beam can throw farther but is more prone to tint shifts. Those tint shifts are also visible in the beam.

• Length: 195 mm / 7.677 ”
• Head diameter: 60.44  mm / 2.38 ”
• Body diameter: 27 mm / 1.064 ”

Weight: 

• Empty: 339.4 g / 11.97 oz
• Including Weltool UB21-50 battery: 413 g / 13.28 oz

LEP Flashlight comparison

Size compared to other LEP flashlights

Image 1, Welltool flashlightsfrom left to right: Weltool W5, Weltool W4 PRO, Weltool W4, Weltool W3 PRO

Image 2,3: Acebeam W30, Weltool W4 PRO, Weltool W4, Jetbeam M1X WP-RX, Astrolux WP2, Jetbeam RRT M1X Raptor, Astrolux WP3, Nextorch T20L, Maxtoch L2K, Lumintop Thor 3.

Weltool uses its own driver and design. The firmware on the W4 PRO is very easy to use.

Available modes:

• Low, High
• Strobe

From OFF:

• Half-press: momentary on
• Single-click: Next mode memory (turned off in Low, next time will be High.. Turned off in High, next time will be low)
• 3+presses: strobe

From ON:

• Single-click: turns off

Shortcuts:

• Strobe: 3 taps from off
• Low: single click
• High: just double-tap from off, and fully click the switch at the second tap.

Mode memory:

• Doesn’t seem to work on mine. It has Next Mode Memory… which is quite horrible.

Blinky modes menu:

• There is a hidden strobe mode. Access by half-pressing the switch 3 times when off. It looks more like a quick breathing pattern than a real on/off blinking.

Low battery warning:

• Not that I could detect.

Lock-out mode:

• No, it’s a mechanical switch, so a full click will turn it off.

PWM:

• No, not visible by eye.

Firmware / UI Conclusion:

Using next-mode-memory is a little mystery to me. I talked to Weltool, and maybe the next batch will start always from Low.

For testing, I used a flat top, non-protected 21700 battery, and that works fine. Both ends use a spring, so that gives you extra room to use different lengths of batteries. Weltool will include a Weltool UB21-50 battery with their W4 PRO. That is a 21700 type battery, with 5,000 mAh capacity and USB-C charging port. The charging cable is likely to be included as well.

Mine didn’t include a battery, so I took the following section from the older W4 review:

The specs on the battery say: 5V 2.0A, and I could only get up to 1.5A. I upgraded my USB charger, in order to read higher numbers, but I couldn’t get past 1.5A on this battery. So I would say it charges at max 1.5A. This means that charging takes about 3+hours.

During the charge, a little indicator LED is visible inside the positive side of the battery. There is a tiny hole with the indicator LED behind it. During the charge, it lights up red, and when finished it turns blue.

Lumen measurements:

All output numbers are relative to my homemade Integrating Sphere. It is set up with an Extech SDL400 Lux Meter for measurements including a Kenko PRO1D ND-16 filter. The base measurement is done with a Convoy S2+ that has been tested at 255 lumens.

All of my readings were taken from a fully-charged brand new Samsung 40T, and a used Weltool UB21-50. The numbers of the 40T were slightly higher, so here you go; with Samsung 40T

Mode	Specs	At turn on	30 seconds
Low	210	201	204
High	568 lm	576 lm	553 lm

Weltool asked us to do the lumen testing, and initially the numbers were about 3% higher. After testing I found out that the battery of the calibration light was low. I replaced the battery and tested it again.

Here are the numbers with the Weltool 21700 battery.

Mode	Specs	At turn on	30 seconds	10 minutes
Low	210	193	197 lm	178
High	568 lm	567	550 lm	514

Parasitic drain:

• Couldn’t measure

Runtime:

The runtime test was done with the 50cm integrating sphere, including the Kenko Pro1D ND-16 filter and Extech SDL400 data logging Lux Meter.

According to the ANSI FL1 standards, the end of a runtime is when the output drops to 10% of the initial measurement (30 seconds after turn on).

Mode	Specified runtime	Measured runtime
Low	4h30min	4h21min
High	1h	1h7min

You can see a little strange behavior towards the end of the runtime in High mode. It’s also interesting to see that there is not so much difference between the 2 21700 batteries. the 5,000mAh battery runs a bit longer.

Throw Measurement

Measurements were done at 4 different distances, 5 meters, 10 meters, 20 meters and 40 meters. The numbers below are from the 20 meters measurements.

Mode	Specifications	Candela measured	Meters	Yards	Miles
High	2,882,000 cd	2,808,000 cd	3351 meters	3665 yards	2.08 miles
Low	1,108,000 cd	1,088,000 cd	2086 meters	2281 yards	1.30 miles

This means it does more than 2 miles

Below: compared to other single-cell LEP flashlights.. You can see how well it performs.. just crazy!

Candela comparison: single-cell LEP flashlights with 60+ mm heads

A list of the larger single-cell LEP flashlights we reviewed: These numbers are NOT from the specifications but are measured by our reviewers. They include all single-cell LEP flashlights with a large diameter head (about 59mm and above). The numbers include the measurement in lumens (lm), measure candela (cd), and calculated distance in meters, and yards. These numbers are all measured 30 seconds after turning on.

Flashlight (click for review)	@30sec (lm)	Candela (cd)	Meters	Yards
Acebeam W30	498	1,312,000	2291	2505
Amutorch BT60	316	1,644,000	2564	2804
Astrolux WP2	303	1,248,000	2234	2443
Astrolux WP3	445	2,412,000	3106	3397
Jetbeam M1X WP-RX	491	2,280,000	3020	3302
Jetbeam RRT M1X Raptor	267	880,000	1876	2052
Lumintop Thor 3	311	1,728,000	2629	2875
Maxtoch L2KS	442	2,308,000	3038	3323
Nextorch T20L	975	1,284,000	2266	2478
NlightD L1	513	1,940,000	2786	3046
Weltool W4	450	2,184,000	2956	3232
Weltool W4 PRO	550	2,808,000	3351	3665

And below is an interactive throw comparison graph (candela), between all single-cell LEP flashlights with a head larger than 45mm. Hover your mouse over the interactive graph below to see the details of each specific light. (tip: hold your mobile phone horizontally to see the full graph)

For the following beamshots I used a Canon EOS 5D Mk2 and a 100mm lens. manual settings: ISO1600, .5sec , F4, 5000K

The tower is about 450 meters / 492 yards away.

Disclaimer: This flashlight was sent to me for review at no cost by Weltool. I have not been paid to review, nor have I been holding back on problems or defects.