In late 2007, I bought a couple of Ultrafire C2 flashlights. They were nicely made for an inexpensive flashlight and they used Cree XR-E LEDs (P4 bin).
Last fall, I modded one of my C2s with a Seoul Semiconductors Z-Power LED P7. The P7 is a quad die LED. I made it direct drive running off a single Li-Ion 18650 battery. There were mods that could be made for a circuit board to drive the P7 but I was too lazy to make one.
I recently found a 3-Mode Regulated Circuit Board for Cree MC-E and SSC P7 LEDs (SKU 1217) sold by Shiningbeam.com that advertises an output current of 2500 mA on high. It has only three modes: high, medium and low. The 17mm diameter of the board is a direct fit in many pills, including a lot of P60s and the Ultrafire C2. I used one of the boards to improve a DealExtreme P60 MC-E drop-in.
I had another of the Shiningbeam boards and a quad die Cree MC-E LED, so I decided to put them in my other Ultrafire C2.
I soldered the LED to a trimmed down DealExtreme Star Connection and Heatsink for Cree MC-E LED Emitters – Parallel (SKU 16545). I’m not sure why they call it a parallel board, because each die is separately addressable with the connections on the board. I soldered all the anodes together and all the cathodes together, so it would run in parallel.
With a fully charged Li-Ion 2400 mAh battery, I measured the current at a little over 2700 mA through the tailcap. After five minutes, the flashlight was hot, but not so hot that I couldn’t touch it. It also dimmed slightly from initial turn-on but it is still brighter than my P60 MC-E mod.
With a McClicky switch in the tailcap, this is a really nice, bright flashlight now.