I also carry one on every dive when doing macro (99% of all my diving), highly recommended. there are 3 sizes so they fit most manufacturers ports (but not all!)
I shove mine in the top of my wetsuit shoving it down my neck opening (not such a good idea in cold waters) as I found it gets in the way and gets scratched elsewhere. This probably why I lose so many though
I shove mine in the top of my wetsuit shoving it down my neck opening (not such a good idea in cold waters) as I found it gets in the way and gets scratched elsewhere. This probably why I lose so many though