Rubber boat valves
Hebor Watersport has dinghy valves available in many different types and sizes. They have an outer part and an inner part that is attached with a valve key.
Depending on the brand, a rubber boat valve has a specific size. If you want to replace a rubber boat valve, it is best to buy a new valve with the same outer diameter as the original valve. This will give you the best chance of the new valve fitting without any problems.