McE2S Two-Stage Tailcap Switch, retail $49 ()
Manufactured by Don McLeish (
Last updated 09-03-04

The McE2S two-stage tailcap switch is a third-party switch designed to fit on your SureFire KL1 or L4 LED flashlight (it is meant for LED flashlights only, not incandescent ones), and is designed specifically to give you two light levels instead of just one.


To use the McE2S tailcap switch, just unscrew and remove the tailcap from your SureFire KL1 or KL4, and screw the McE2S tailcap on. Be sure to unscrew it slightly when your KL1 or L4 springs to life, so you don't waste the batteries.

Press the rubberised button lightly and hold it that way to get low-level light; press it more firmly and hold it to get full output. Release the button to turn the flashlight off. This is momentary mode.

Turn the tailcap clockwise (as if tightening it) until the light comes on in "low" mode; turn it clockwise some more to get full output. Turn the tailcap counterclockwise (as if loosening it) to turn the light off - first it will go to "low" mode, and then it will shut off. This is continuous mode.

This product does not use batteries in and of itself; so this section can and will be skipped.

The above photograph shows the McE2S switch installed on a SureFire KL1 flashlight (KL1 bezel, E2e body, powered by two CR123A lithium cells).

The McE2S-equipped KL1 or L4 would retains all of their weather-resistance. When I suctioned the spring-end of the McE2S and operated the button several times, air was not admitted through it.

The McE2S is finished with a Type III hard anodized covering ("HA-III" as us flashaholics know it), and is as tough as the SureFire flashlight you put it on. So if you are looking for a possible mismatch, you won't find it here.
There is a slight color mismatch, however this is perfectly normal with the HA-III process, and will not be a problem.

As for overall durability, that isn't a problem either. I smacked a McE2S-equipped KL1 against a steel rod at the switch-end five times, and caused no malfunction, and caused no detectable damage either.

The model I have is equipped with a 22 ohm resistor for "low" mode; you can get these with 15 ohm, 30 ohm, and 60 ohm resistors too.
Higher resistor values will always equal lower light levels in "low" mode.

Beam photo of McE2S-equipped KL1 ("low") at ~12".
Measures 96,600mcd.

Beam photo of McE2S-equipped KL1 ("high") at ~12".
Measures 300,000mcd.

Both measurements were taken on a Meterman LM631 light meter, with batteries of unknown prior usage. I'm currently out of CR123A cells, and do not have the money to buy any more.

I believe the KL1 should measure 351,000mcd on "high",
as that's what it measures by itself with new cells.

Test sample of the McE2S two-stage tailcap switch was sent by Don McLeish ("McGizmo" on Candlepower Forums) and was received on 07-27-04.
More information about this switch can be found at

Product is homemade and will not be rated like a commercial product.
If I were to rate this product however, I would not forsee giving it any less than 4 1/2 stars.

UPDATE: 08-28-04
Because this is a switch, rather than a flashlight or other article that emits light, the conventional "star" rating will not be used.
It is also homemade, and will not be rated like a commercially-produced product.

UPDATE: 09-03-04
My SureFire KL4 turned up a few days ago, and just now, I remembered I had the McE2S switch on a SureFire KL1.
Now that it's where it *really* belongs, let's try some more tests...

KL4 on "high": 500,000mcd
KL4 on "low":  52,400mcd

Known-new BatteryStation brand CR123A cells were used for this test.

    PRODUCT TYPE: Tailcap switch for SureFire KL1 or KL4
    No. OF LAMPS: N/A
    SWITCH TYPE: Two-stage, push for momentary, twist for continuous
    BEZEL: N/A
    SUBMERSIBLE: Yes, depth rating not known
    WARRANTY: Unknown/TBA

    Product is homemade and will not be rated like a commercial product.

McE2S Two-Stage Tailcap Switch *

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