I bought 2 for the waterproof cases. I submerged it in water and it didn't get wet. The lid should also have grooves because it slips a little when it's wet. It can fit almost a matchbox inside. The reflector and whistle work quite well, as do the compasses, but if you find yourself in a situation where you need a compass, get a regular one. The cord is quite long. The flint on the side doesn't even have the thickness of a toothpick; just say it's not there and you're good to go.