Mellert MasterLED x4, retail TBA (
Manufactured by Mellert SLT GmbH & Co KG (
Last updated 03-04-07

When you first receive one of these flashlights, you might think it's a knockoff of the Lightwave 2000, but look again. Housed in a black plastic case, the MasterLED x4 features special lenses moulded right in the bezel to focus the four LED beams into a single, moon-like circle of white light from a couple of inches on out. A black, rubbery pushbutton on the light's barrel lets you turn the light on and off, and the whole thing feeds from 3 AA cells.

It comes with an elastic wrist lanyard, already attached. You can either use it or just ignore it.


To use the MasterLED x4, first get it out of the package by slitting down one side with a knife or razor blade. Then, feed it (see below), and it'll be ready to use.

Press the button on the barrel until it clicks to get light, press it again until it clicks to not get light.

There is no momentary mode when the light is off, but you can blink the MasterLED while it is on, by pushing the button partway in but before it clicks.

To change the batteries in the MasterLED x4, unscrew & remove the head, and set it aside.
If there are any dead batteries in the barrel, dump them out and dispose of them how you see fit. Place three new cells in the barrel, button (+) side facing you (facing outward). Screw the head back on, and tighten it hand-tight. Be sure your dead batteries are all disposed of, and there, you're done. That wasn't hard now, was it?

Due to the way the flashlight was made, I am unable to get a current measurement.

(That whitish thing in the center is an artifact created by the camera flash - it is not present in the flashlight itself.)

The MasterLED 4x appears to be reasonably tough and durable - this isn't your everyday $1.99 drugstore flashlight here. I ran over it with a 400 pound electric wheelchair, and no breakage was found to have occurred. I also struck its barrel and head against a steel rod and a thick metal tripod leg, and no damage was found then either.
Right below, is a picture of it being run over with an electric wheelchair.

I don't often show pictures of lights under the wheels of my 400 pound Rascal 245 (with me in it driving back and forth over the flashlights for the tests themselves), but I think it was appropriate here.
(Well, OK...I was specifically asked to run over this flashlight!)

There is a lubricated O-ring in the head assembly, so it ought to be water-resistant at very least. The package claims it is submersible (waterproof) to 3 feet (1 meter), and I have no reason to doubt those claims. So it should stay dry inside if it falls in a toilet bowl or if it's used outdoors in a hurricane or other storm.

The beam from this light is different than most, in that instead of a central bluish white hotspot with a soft fall-off toward the edges, it produces a round central area with a very abrupt edge; characteristic of other lensed LED flashlights except there are no lines or other junk in the beam.
The lenses also narrow and brighten the beam, so it reads brighter on a meter than it might without lenses. So don't be alarmed at the 83,000mcd reading, and think the LEDs are being seriously overdriven. I don't think they are, so you should get a long and useful life out of them. The beam is wider (by more than double) than that found in other lensed LED flashlights. The four LED beams coalesce into a single circle at about 2" to 3" (about 8cm), so you can use it to poke around inside computers and other tight spaces.

The MasterLED x4 feels good in the hand. There are some ribs around the barrel near the switch; these help you "keep a grip on things" even if your hands are cold, wet, or oily. But they don't feel uncomfortable - at least not during the short time I've had this flashlight.
There are also ribs on the flashlight's head to help you remove & replace it for battery changes.

Beam photo at ~12".
Measures 83,000mcd on a Meterman LM631 light meter.
This is not an unusually high value, considering the LEDs are focused with lenses.

Spectrographic plot
Spectrometer plot of the LEDs in this flashlight.
Ocean Optics USB2000 Spectrometer on loan from TWO-CUBED.

ProMetric analysis
Beam cross-sectional analysis.
Image made using the ProMetric System by Radiant Imaging.

Test unit was received around 09-20-03, and is in its initial stages of testing.

The website is in German, so you'll probably want to run it through the translation matrix of your choosing if you do not understand that language.

UPDATE: 09-30-03
The threads used for screwing the head onto the body are fairly fine in pitch, so it is possible to crossthread the head when you're screwing it on. If the head stops spinning freely shortly after you start putting it on, you've probably gotten it crossthreaded. Unscrew it, and be sure it goes on straight when you screw it on again.

A suction test did show there's substantial leakage around the switch, so the flashlight should be considered "weather resistant" rather than "waterproof". The packaging claims 3 feet (1 meter) of submersibility; your results may vary.

UPDATE: 10-17-03
I heard from the manufacturer earlier today, and the switch leakage issue was indeed a fluke. Less than 1% of production units leak in this manner, so I guess I just got unlucky. If yours leaks around the switch, it should be covered under warranty, so I have no reason to believe this will show up in the rating I give this flashlight.

Bright, focused beam
Durable case
Advertised as being water resistant & submersible to 3'
Feels nice in the hand

May not be totally water resistant, but see 10-17-03 update above
Very little spill light; some users may find this objectionable (there goes half the star)
Not regulated (and there goes the other half)

    MANUFACTURER: Mellert SLT GmbH & Co KG
    PRODUCT TYPE: Handheld flashlight
    LAMP TYPE: White LED
    No. OF LAMPS: 4
    BEAM TYPE: Circular, with an abrupt edge
    SWITCH TYPE: Pushbutton on/off on barrel
    BEZEL: LEDs behind custom lenses in bezel
    BATTERY: 3 AA cells
    CURRENT CONSUMPTION: Unknown/unable to measure
    WATER RESISTANT: Yes (weather-resistant)
    SUBMERSIBLE: Yes, to 3 feet (advertised)
    ACCESSORIES: Wrist lanyard
    WARRANTY: 2 years


    Star Rating

Mellert MasterLED X4 TL 266 *

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