Disregard this at your peril. You could pay 3 quid for any of the functions. The whistle is loud, compass accurate, flint is handy, mirror signaling device, A lanyard(bootlace,guy rope etc). But it's the waterproof cylinder that really impressed me - I fit a Opinel No2 in there, 2trusted fly lures, split shot, hooks, line, needle and cotton, half a dozen matches(can be used as a float), a to stop it shaking a piece of cotton wool. Now if only I could stop the bl**dy pea from rattlening.