Elcheapo version: I have a cannon sureshot owl I got from skydance, It was already fitted with a thumb release and a 3.5mm jack (I think, I measured it???) The thumb release was not very conducive to skydiving because you would have to thread the cable down the sleeve of your jumpsuit etc. (unless I cut the wire in the middle and added a plug) but I really wanted to have something that was 'hands free'. The switch I bought was the long skinny one from paragear, most of the other vidiots I know use the flat round one...first clue:( I had a senior camera flyer splice the two together and it worked ok, I never could get a consistent 'bite' though so it took a few squeezes to get it to fire each time. He saudered the wires together, I think right. Anyway, when I put it all in my helmet it stopped working....so I guess I either shorted something or lost a connection when taping all the excess and jack to my helmet...or the switch gave out, maybe why it was so difficult to get it to work in the first place...Thanks in advance!!!