Weltool LH1 Tactical Flashlight Review

Weltool LH1 Tactical Flashlight Review

Weltool makes quite a few impressive flashlights and the LH1 Tactical head is no exception.  The LH1 is a head that fits multiple bodies, including a W35 weapon light body, and others.  Read on for testing!

Official Specs and Features

Here’s a link to the Weltool LH1 Tactical head product page.  The bodies seen here are separate products.  The W35 is a weapon mount body.  The BB3 with TC59 tailcap is an 18650 EDC-type tactical body.  Both work with the Weltool LH1 Tactical head.


There is just one version of the LH1 but it’s available in black or FDE (seen here).


The LH1 head retails for $128.  Bodies are separate purchases.  Since this is a LEGO, you will need to buy a body and maybe a tailcap separately.  The W35 body has a tailcap included ($30), and the BB3 has the TC59 tailcap included too ($44.)

Short Review

Two points to short-review about.  First, simply as a flashlight, the Weltool LH1 Tactical head is great.  Just one mode, no-nonsense, and exceptionally well built.  Secondly as a weapon-mounted light with the W35 body:  again a winner.  The light fits as it should, has Surefire compatibility, and works properly.

I should probably say up front that while I have some photos of this light with the W35 body weapon-mounted, I’m not super knowledgeable about that side of things.  So I’m testing this primarily as a flashlight first and secondly, you can view some mounted photos and likely draw your own information.

Long Review

The Big Table

Weltool LH1 Tactical Head
Emitter: Osram KW CSLNM1.TG (CW)
Price in USD at publication time: $128.00
Cell: 1×18350
18350 Runtime Graph 18650 Runtime Graph
LVP? Yes
Switch Type: Mechanical
On-Board Charging? Yes
Charge Port Type: micro-USB
Charge Graph of included 18350 cell
Power off Charge Port
Claimed Lumens (lm) 686
Measured Lumens (at 30s) 564 (82.2% of claim)^
Candela per Lumen 156.8
Claimed Throw (m) 598.7
Candela (Calculated) in cd (at 30s) 4080lux @ 4.671m = 89018cd
Throw (Calculated) (m) 596.7 (99.7% of claim)^
All my Weltool reviews!

^ Measurement disclaimer:  Testing flashlights is my hobby. I use hobbyist-level equipment for testing, including some I made myself. Try not to get buried in the details of manufacturer specifications versus measurements recorded here; A certain amount of difference (say, 10 or 15%) is perfectly reasonable.

What’s Included

Weltool LH1 Tactical what's included

I received the “retail package not retail package” version of the LH1.  I received the LH1 with the W35 body, and a Weltoll 18350 (1200mAh, with micro-USB charging).  I also received the BB3 18650 body with TC59 tailcap.  Essentially all of those are separate item purchases, so my package isn’t really representative of what you’ll get.

Weltool LH1 Tactical what was included with my kit

Basically, the Weltool LH1 Tactical flashlight is a LEGO weapon-mounted flashlight, and you will either have the parts you need to go with the head or can see in this review what you’ll need.

Package and Manual

Weltool LH1 Tactical box

I should be able to add a manual here soon, but overall I’d call the light simple enough that you won’t need it.

Build Quality and Disassembly of the Weltool LH1 Tactical and Parts

Starting right about here I should mention that I have two bodies for the Weltool LH1 Tactical head.  But this is broadly a review of the LH1 head, with some “bonus footage” of the two bodies – the W35 and BB3/TC59.  In all cases, I will talk about the W35 first, followed by the BB3/TC59 if applicable.

Weltool LH1 Tactical feature photo

The Weltool LH1 Tactical flashlight is an aluminum body light, available in black and FDE (flat dark earth) (seen here).  I have the matching W35 body, which has screw holes for mounting directly to a weapon.

You’ll see why I say this later, but the Weltool LH1 Tactical head is of exceptional quality.  These two bodies are as well, but the LH1 is above and beyond.

My BB3 body, which supports a single 18650 cell is black anodized, so doesn’t match my FDE LH1 head.

18650 feature photo

Build quality of this body is also great, but I would put it just below the exceptional level of the W35.  Still fantastic, but feels much simpler.  (It’s the knurling, in particular.)

The tailcap of the W35 body is standard.  Per the Weltool product page:

The tail of the body can be fitted with Weltool TC68, TC69, TC70 and other Tailcaps. It is also compatible with surefire Z68 Tailcap, DS00 or UE Rear Cap, so you can use the corresponding Remote Switch such as surefire ST07.

I don’t have many Surefire parts, but I do have one light that’s CR123x2.  This tailcap fit it perfectly.


Note that long spring.  It’s a good spring, and good springs are important in weapon-mount lights.

tailcap removed

And not just a spring – there’s a nice o-ring bumper there, too.

tailcap spring

Here you can better see the lego nature of this light.  The head fits on [some] body, and the body fits with [some] tailcap (in this case the included tailcap).

LH1 head W35 body

In fact, let’s just have a look at Weltool’s product lines… This graphic is very explanatory.

weltool products

As you can see, there are a bunch of options!

head threads

Both head and tail have unanodized threads.  This means loosening them will not turn off or mechanically lock out the light.  But with a mechanical switch, this is no concern at all.  In fact, this is better for a tactical light – bare threads being used for contact helps ensure that recoil will not break contact.  The light will stay on while mounted to your weapon.

head off cell installed

Now on to why I think the Weltool LH1 Tactical head is so well built.  Have a look at these contacts.  Brass.  Beefy.  That retaining ring is of the absolute highest quality that I can remember seeing.

head and tail springs

The head has a spring too – dual springs are mandatory in weapon mount lights.

BB3 body 18650 BB3 threads

One of the main differences in the BB3 body is that the tail end accepts a different size tailcap.

BB3 tailcap

This tailcap is a standard size – here’s what Weltool says about it:

This TC59 is a 1-inch diameter Click-On Lock-Out switch tailcap, compatible with Surefire 6P, 9P, C2, C3, Z2, L5, M2, M3, M3T,6PX and other flashlights.It can replace Z41, Z58, Z59 tail covers.Can withstand 4A current.

tailcap spring

Again the spring here is long and beefy.

Here are my Lego parts for this Weltool LH1 Tactical head.  One head, two bodies, and two tailcaps.

LEGO body parts

Size and Comps

The Weltool LH1 Tactical head is 32.5mm in diameter.

If the flashlight will headstand, I’ll show it here (usually the third photo).  If the flashlight will tailstand, I’ll show that here, too (usually the fourth photo).

W35 in hand

You won’t really be using the W35 as an EDC style light, since it has these mounting holes.  But it is very flashlighty, and that makes it great.  I believe Weltool has or will have an 18350 body without the mounts – the BB6.

W35 in hand

Here’s the test light with the venerable Convoy S2+.  Mine’s a custom “baked” edition Nichia 219b triple.  A very nice 18650 light.

You can’t really say either of these bodies makes the light short, but you sort of have to work around the constraints of standardized sizes.  So it is what it is.

And here’s the light beside my custom engraved TorchLAB BOSS 35, an 18350 light.  I reviewed the aluminum version of that light in both 35 and 70 formats.

beside torchlab boss 35

beside torchlab boss 35

Retention and Carry

For the W35, I had to purchase a Picatinny mount.  I just found some random inexpensive one.  This cost me around $12.

rail mount

I’d never used one of these before, but fitting it couldn’t really be simpler.

rail mounting

Use the two included screws to mount the bracket to the flashlight (specifically the W35 body).

rail mounting

It should look like this when done.

Then locate the Picatinny rail on your weapon.  I have rails all over this weapon, so I was good to go.

Picatinny rail

In my case, I had to slide the connector on from the back, since there is something mounted in front.

Picatinny rail

Slide the flashlight to the desired “forwardness.”  You’ll need to have the screw and tooth completely removed for this.

Picatinny rail install

When these parts are where you want them, throw that screw in there.  Mine is a hex screw, and yours probably will be too (probably a standard?  Not really sure).  Either way, my adapter bracket shipped with the appropriate two hex drivers.

Picatinny rail install

Tighten it down!  Only tighten it according to your willingness for the whole thing to fall off during use.  (Ie tighten it down very well).

Picatinny rail installed

mounted on crosman dpms sbr

First time I’ve featured this here on my site.  I’m not sure if this reduces my “family-friendly” status but I should point out that this is a BB gun!  I searched for ages to find a … well to be honest it’s a prop… I searched for ages to find the right prop, which uses real rails that I can use for exactly this scenario.  You want to see what a gun light looks like mounted.  Well, here we go!

weltool lh1 with w35 on crosman dpms sbr

I hope you’ll abide by me using a bb gun for these photos, but I have to report that it’s a full auto bb gun, so it’s very awesome.

on crosman dpms sbr

For the record, this is a Crosman DPMS SBR.

on crosman dpms sbr on crosman dpms sbr on crosman dpms sbr

on crosman dpms sbr on crosman dpms sbr

The BB3 body, of course, is not a weapon mount body.  Or at least, not in the W35 way.  You could mount it some other way; the body is certainly able to withstand that type of use.

But with the BB3, the main carry will be the included friction fit pocket clip.  This clip isn’t reversible, nor is the body.

bb3 pocket clip

Power and Runtime

No matter what body you use with the Weltool LH1 Tactical head, you’ll only want to use one lithium-ion cell.  In the case of the W35, you’ll use a single 18350 cell.

18350 w35

I had a cell included and tested the light with this cell.  The cell fits into the light in the usual way – positive terminal toward the head.  The Weltool 18350 is a button top, but with such nice and long springs, any type 18350 should work just fine.

18350 in w35

Important note about a mounted W35 – with the light mounted, it’s possible to remove the LH1 and swap cells.  It’s not necessary to remove the light from your weapon.

head off while mounted

head off while mounted

head off while mounted

On the tailcap end, the cell is captured.  I’m sure there’s a historical reason for this, but I don’t know it.  I’m sure some gun nuts can tell!  For one thing, it has to do with the narrowness of this standard-sized tailcap.  18350 in w35

Here’s a runtime with the included 18350 cell.  The light has only one mode, so here’s just one runtime with that cell.

runtime graph 18350

I also performed a runtime with the BB3 body, and a Samsung 30Q 18650.  The graph looks exactly the same, and the performance is identical too.

runtime graph 18650

The light does maintain initial output for a few minutes, then steps down to around 300 lumens until starting to taper off because of low cell voltage.  Shutoff is around 2.8V, which is good for the cell – whether that’s good in a tactical application is something you’ll have to decide.

Based on the product page, it seems that the Weltool LH1 Tactical head will not support two-up of any cell type.  Certainly not two 18350 cells in the BB3 body, but also not 2x CR123 cells (which would have a much lower voltage than 2×18350.)  So just one cell, always.  (I prefer that anyway, as it’s been proven historically safer.)


Since the Weltool 18350 has built-in micro-USB charging, I went ahead and ran a graph of that.  Charging is at over half an amp and requires just under 2 hours.  Not too bad.

charge graph for included 18350

Modes and Currents

Mode Mode Claimed Output (lm) Claimed Runtime Measured Lumens Tailcap Amps
On 686 (Depends on body) 564 3.31

Pulse Width Modulation

No PWM at all on the only mode.

pwm graph

For reference, here’s a baseline shot, with all the room lights off and almost nothing hitting the sensor.  Also, here’s the light with the worst PWM I could find.  I’m adding multiple timescales, so it’ll be easier to compare to the test light.  Unfortunately, the PWM on this light is so bad that it doesn’t even work with my normal scale, which is 50 microseconds (50us). 10ms5ms2ms1ms0.5ms0.2ms.  In a display faster than 0.2ms or so, the on/off cycle is more than one screen, so it’d just (very incorrectly) look like a flat line.  I wrote more about this Ultrafire WF-602C flashlight and explained a little about PWM too.

User Interface and Operation

I would say that the user interface is going to depend on the body you use, but in truth, these should all be forward mechanical clickies.  There might be some twisties out there?  But surely not in a tactical light.

w35 switch

The switch on the W35 body is protected around the edges.

The switch on the TC59 tailcap (for the BB3 body) is very proud, and like the W35 tailcap, has a very positive clicky action.

bb3 switch

Surefire offers some remote switches that can fit certain Surefire tailcaps, too.

Here’s a UI table!

State Action Result
Off Click On
On Click Off

I mean, as far as simple goes…..

LED and Beam

The emitter in the Weltool LH1 Tactical head is an Osram KW CSLNM1.TG, and it’s cool white. 

osram emitter

The reflector is smooth and deep, and fairly broad.  You can see below the resulting beam profile – tight, with minimal spill.

uncalibrated beamshot

LED Color Report (CRI and CCT)


These beamshots are always with the following settings:  f8, ISO100, 0.3s shutter, and manual 5000K exposure.
beam shot on ceiling

Tint vs BLF-348 (KillzoneFlashlights.com 219b version) (affiliate link)

I keep the test flashlight on the left, and the BLF-348 reference flashlight on the right.

beamshot on door compared to nichia 219b

I compare everything to the KillzoneFlashlights.com 219b BLF-348 because it’s inexpensive and has the best tint!


What I like

  • Exceptional build quality
  • Lego options for bodies and tailcaps
  • Surefire compatibility
  • Only one mode
  • Great beam profile for the application

What I don’t like

  • Stepdown after a few minutes.  (Give me 10 or so minutes at the initial output, then step it down.)


  • This light was provided by Weltool for review. I was not paid to write this review.
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1 thought on “Weltool LH1 Tactical Flashlight Review”

  1. “Dual springs are mandatory in weapon mount lights.”
    Streamlight HL-X has entered the chat

    As for the historical reason for the switch size, I know it originated when CR123A batteries were the only power source for that size light, but I don’t actually have a Surefire tube on hand to confirm whether you can or can’t swap those cells through the tail cap. In any event, if you have a tape switch on the light it’s easier to swap cells through the head end anyway.

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