Chances are your light or other piece of gear came with a wrist lanyard. This item is probably ok for diving in the tropics where you shouldn't be doing anything with your hands anyway, but around here it is lousy. Wrist lanyards are a pain to put on and a pain to get off, and in the case of a light, if you let go of it to do something with both hands, it will invariably get in the way and bob around until it shines in your eyes and blinds you. When you finally get fed up with it, you will take it off, and in a careless moment, your equipment will be lost. Here is a much better rig, commonly known as a "hi-lo" lanyard:
Take the wrist lanyard off, and throw it away. Get two brass snaps and a piece of rope. Braided 1/2 " nylon is what I used because it is supple, won't rot, won't unravel, and doesn't float. Attach a brass snap to each end. You can just tie them on, or get fancy like me and make streamlined loops. The end-to-end length of mine is about four feet, including the snaps, but you can experiment. Attach the base ring of one of the brass snaps directly to your gear where the lanyard was.
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