Fat:i use the Atomic M1 its a great reg and the only thing u need to have done to it is put a cave ring on. All my tech 1 and cave 1 tech guys that i dive with use them i just wish that they were o2 cleaned to 100% but there good up to 80%
What's a "cave ring"? If it's good to 80% then why isn't it good for 100%?