Weltool W4

Weltool W4 review

Weltool W4 pecifications:

Brand / ModelWeltool W4
Lumens560 Lm
Beam intensity1.782,000 cd
Battery config.1*21700
Review dateJuly 2020


The Weltool LEP’s have been on my list since they were announced. I never got the original W3, but I’m glad I can finally say that I own the latest generation LEP flashlights with an impressive beam distance of up to 2670 meters (1.66 miles). We are talking about the Weltool W4.

Is this really the next king of throw in the consumer LEP market?

What you’ll get:

The packaging looks professional and is designed specifically for this flashlight. Unlike some cheaper brands that have simple white or brown carton boxes. And this type of specially designed packaging is what I expect from a good brand.

  • The flashlight: Weltool W4
  • Large Laser warning
  • 1 spare o-ring
  • Weltool 21700 battery UB21-50 (5000 mAh)
  • USB-C cord

Handling of the light

The Weltool W4 feels great in my hands. Enough knurling and the pocket clip helps with the grip. There is only 1 switch, at the rear. The tail switch is forward-clicky and feels like any other high-quality switch. Nothing to complain about.

One thing I don’t really understand is the pocket clip with this size of light. I just can’t imagine anybody using it. Instead of a pocket clip, I think a lanyard or a holster would have been a better fit, no? I wonder what you guys think about this.

The W4 should be easy to operate with gloves by the way. The tail switch is protruded and not shrouded. And that is done for a reason. This thing is meant to be used for hunters or search-and-rescue. It also means that you can’t tailstand it.

Build Quality, knurling, threads, and anodization

I bought the Weltool W4 together with the W3 PRO and they are my 3rd and 4th Weltool flashlights. And what I noticed is its knurling. If you look up close you can see that this is a special Weltool characteristic. Not sure if you notice it in the pictures below. But have a look and I think you can see what I’m talking about.

Threads near the head are bare aluminum and protected from water by a black O-ring. The o-ring is not lubed, unfortunately. Or maybe I have unscrewed it too often? Anyways, you should double-check whether yours is lubed since this should help increase its waterproofness.

The rear threads are anodized and lubed, and the threads are protected by 2 black o-rings that are well lubed.

I also really like the matte finish of the anodization. It’s much better than some other popular brands that choose a more shiny coating. And I can’t find any blemish on the body, tailcap or head.

I hoped to see a few more accessories with the W4 though.

LEP, Lens, Bezel, and Reflector

Since we are reviewing a white laser flashlight and not an LED flashlight, I can’t really show any pictures on the inside. It’s impossible to unscrew the bezel by hand so I guess it’s glued.

The bezel is made of stainless steel and makes it more impact resistant. There is no reflector built into LEP flashlights so no comments on that. And according to the manual, it has a tempered glass lens. I’m not sure if it looks like all LEP flashlights have darker lenses or that it’s simply because of the lack of a shiny reflector. It could possibly be the latter.

On the head, near the bezel, there is a warning displayed. It says Warning, Class 3B Laser Product.

This warning is also very apparent when opening the Weltool W4 box. The first thing you see inside the box is a large Laser Warning. Take a look at the pictures yourself. This would be enough warnings for people.

These types of laser flashlights are never meant to be used by children. In the product description, you can also read that you shouldn’t use the light more than 10 minutes at a time. Of course, I have done runtime tests that will largely exceed the 10 minutes, to see how it performs in the long run.


  • Length: 190 mm ( 7.48 “)
  • Head diameter:  60.55 mm ( 2.384 “)
  • Body diameter: 26.99 mm ( 1.062 “)


  • Empty:  333.3 g ( 11.76 oz)
  • With battery: 407 g ( 14.36 oz)

LEP Flashlights

From left to right: Acebeam W30Weltool W4, Jetbeam RRT M1X raptor, Jetbeam M1X WP-RX, No-brand 26650 LEP, Nextorch T10L, Jetbeam RRT M2S, Jetbeam M2S WP-RX, Weltool W3 PROFenix TK30, Nextorch T7L, Acebeam W10 gen2.

Driver & User Interface:

LEP drivers aren’t as advanced as the ones found in LED flashlights these days. Sometimes it’s really refreshing to see the simplest User Interfaces possible.

Available modes:

  • High and Low

From OFF:

  • Half-press: Momentary On (and change modes)
  • Full single-click: High

From ON:

  • Single-click: Off

Mode memory:

  • No, it doesn’t have any mode memory. It will always start in High.
  • I like that since you always know in what mode the light will start.

Blinky modes menu:

  • None

Low battery warning:

  • The light will start flashing with low battery voltage.

Lock-out mode:

  • It doesn’t have an electronic side switch, so you don’t have any parasitic drain. For your own safety, you can unscrew the tailcap a half turn to break any electric loop.


  • Not visible by eye.

Batteries and charging:

Weltool includes a high capacity, 21700 battery. It looks like more and more manufacturers are doing this since that guarantees the highest performance of their flashlights. The Weltool battery has a product number: UB21-50. It’s a 5000mAh protected 21700 battery with a USB-C charge port. Not sure if you can charge USB C- USB C, but at least they included a normal USBA to USBC cable.

The specs on the battery say: 5V 2.0A, I could only get 1.5A. I upgraded my USB charger to a 3A one recently, 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.

Since both, the tailcap and driver use springs, it also accepts flat top, unprotected batteries.

The light turns off when the battery is still at 3V. So I expect the built-in LVP (Low Voltage Protection) to have kicked in during the tests instead of the battery’s protection kicking in.


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 is tested at 255 lumens.

All of my readings are taken with a fully-charged Weltool 21700 UB21-50.

Amps are measured with a Fluke 77III, at the tailcap.

ModeAmp at startSpecsat turn on30 sec
high3.10 A560473 lm450
low0.93 A187145

Lumens are lower than expected. This could be because of the integrating sphere in combination with a very, very tight hotspot. I shined the flashlight around in the sphere to get any higher readings, but couldn’t.


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

Weltool W4 runtime graph

High lasts about 2 hours, but as you can see it has some difficulty staying at a certain output. The product description recommends not to use it more than 10 minutes at a time. The drops might be heat-related. The runtime is spot on with the description.

Low mode lasts for 4 hours and 26 minutes. This is a little shorter than the manual says.

Throw measurement:

Measurements were taken both indoors and outdoors with a professional Hagner E4-X Lux Meter. I took measurements at both 5m for indoors and 10m for outdoors. They are roughly measured around 30 seconds. 

Measured at 20 meters I get the following results:

  • High (20m):  2.184,000 cd =  2956 meters / 3232 yards
  • Low (20m):  736,000 cd = 1716 meters /1876 yards

This means that both High and Low perform better than specs. Specs have High at 1.78 Mcd and Low at 603 kcd.

It’s essential to look at the runtime graph of all the extreme LEP flashlights to see how they stack up against each other. The W4 is doing a fantastic job. Although starting at a lower intensity, it throws farther than its competitors for 80% of its runtime.

I calculated candela with the numbers from the runtime graph and used 30 seconds as the base.

Runtime graph of 3 popular white laser flashlights

Beamshots: Weltool W4 vs Acebeam W30

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

The first tower is 650 meters / 710 yards away. The 2nd set of pictures shows a tower at roughly 450 meters / 492 yards.

The 3rd set of pictures shows just a street with trees to indicate medium-range capabilities and beam pattern.

Disclaimer: This flashlight was bought with my own money. I have not been paid to review, nor have I been holding back on problems or defects.

Overall conclusion


  1. High quality
  2. Performs better than advertised (in terms of throw)
  3. Extremely long-range capabilities (3 km)
  4. Includes a high capacity battery
  5. Simple UI


  1. The runtime graph shows many drops, which might be heat-related. Outside temps could actually help sustain output longer.
  2. No additional accessories like holster, lanyard etc.
Author Marco
Author Marco

Rating: 5 stars ★★★★★

There isn’t much about the W4 that is worth complaining about. Although the lumen measurement for high was a little less than expected, the beam distance, on the other hand, are exceeding expectation. Instead of the advertised 1.78 Mcd, mine actually did almost 2.2 Mcd. Just a little less than the Jetbeam M1X at startup. The runtime graph of the W4 indicates this is a great performer! If you don’t own an LEP yet, you will not be disappointed with the Weltool W4.

Weltool W4 for sale

The Weltool W4 is no longer in production. Have a look at its successor, the Weltool W4 PRO instead.

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