What do you carry with you when diving?

[icechip]

Thanks for the replies. It seems to me that there are 3 necessities

1- Something to cut line/rope
2- Something to signal with visually on the surface
3- Something to signal with audibly when on the surface

With a Light Source being a 4th, necessary with backup for night dives, or optional if you're into looking into little caves during day dives.

A snorkel could be useful as well, but is more Dive Specific.

What I'm trying to do is plan for eventualities that I may encounter in diving, taking into account what kind of diving I do.

I'm aware that different dives require different equipment, but I figured that learning from others experiences is helpful to everyone.

I usually go with a whistle zip-tied on the inflator hose, a DGX light, mesh carry bag, smb and a knife.