Quick Facts and Tips 
O RINGS on a scuba tank create an air tight seal between the scuba tank valve and the first stage of a scuba regulator. Buna-N is a common trade name for nitrile rubber, while Viton is a trade name for Fluorocarbon rubber. Viton has better chemical and temperature resistance than Buna, but Buna is usually less expensive. Viton O -rings are 02 Compatible – Buna rings are not.

Did you know?
O-rings will naturally degrade with use or due to exposure to sunlight and salt air. It is advisable to keep several fresh ones with you in a dive kit. You never know when your tanks o-ring may need replacement.