A mono valve is a valve with 1 connection point. A double valve has 2 connection points. A second connection can be fitted with a single valve with an extra port or with a lateral valve. A lateral valve is used for double set set-ups. You will always need a left and right valve with a manifold.
Working pressure of the valve. Note that the cylinder needs to have the same working pressure!
Standard O-rings are suitable when using air. Viton O-rings are used when diving with Nitrox- Enriched air. However, they can also be used with air. Viton O-rings are generally recommended.
The cylinder screw thread is the type of screw thread within the neck of the bottle. This needs to be the precise thread that matches the thread on the valve. NOTE: M25 valves may fit in a 3/4g thread when applying a little pressure. Please DO NOT use this combination. Pictures may not always correspond with the thread features. Please use the filters on the left hand side to choose the correct valves.
This is the screw thread of the valve where the 1st stage is connected. G5/8 is the standard screw thread. M26 is the screw thread which is wider, and is specifically used for Nitrox regsets with the same screw thread- NOTE: M26 is the EU standard for NX
