I bought the M61 with the intention of modding it with the Shiningbeam three-mode regulated circuit board (NLA). The Cree XP-G had recently noted an “increase of maximum forward current to 1500 mA for XLamp XP-G Cool White is retroactive and applies to all XLamp XP-G Cool White LEDs produced by Cree. The increase is the result of more extensive qualification testing that was performed after the initial product launch.” The Shiningbeam board output current is 60 mA on low, 440 mA on medium and 1.4 A on high.
First, I removed the potting and contact spring. In the process, I destroyed the Malkoff driver board. I used a Dremel to reduce the diameter of the Shiningbeam board so it would fit inside the drop-in.
The Shiningbeam board works as advertised – I measured 1.4 A on high, 450 mA on medium and 65 mA on low. I’m not enamored with the yellow-green tint of the LED; maybe I’ll replace it down the line.
I have also used the Shiningbeam board in a DealExtreme XP-G R5 drop-in (SKU 32954). The result, compared to the Malkoff, is a little more throw and a lot less spill. The tint of the DealExtreme LED is also cooler – more blue.
After disassembling the M61, it’s clear that this is a most robust, superbly constructed drop-in. I can see why a professional would be able to rely on this drop-in in a life or death situation. But flashlights for me are a hobby, which is why I wanted to mod this drop-in to have (a more useful for me) three modes. (Note: Malkoff Devices now makes a three mode M361 P60 style drop-in that has an input voltage of 3.4-6 volts)