heres the catch. After you unscrew the retaining ring it is still stuck hanging loosesly on the diode pins between the diode and the circuit board. You can easily desolder the pins from the circuit board and remove the diode, retaining ring, and circuit board. When you install a new diode you need to either solder extention pins onto the small pins from the new diode, or just solder on wires. If you choose wires, you are going to have to come up with some way to stablize the circuit board so that pressing the button will not push it down. I extended the pins when I did a diode swap and it worked fine, I added epoxy to hold the board super stable just in case. I have one now that is doing over 200mW with a diode swap. I also adjusted the focal point so that it will be focussed at like 10 ft. This still gives me a nice dot for distance.
