The protective ring prevents gravel, mud and ice from collecting round the rubber ring and on sealing surfaces of the socket. Removal of the ring is easily achieved by pulling a handle of tape protruding from the ring, (protective polystyrene ring already removed in illustration below).

Retaining sections 3 & 4 ensure that the sealing ring stays firmly in position in the socket.

The sealing section 1 is a lip which presses against the spigot end when this is inserted into the socket.

The compression section 2 prevents concrete to concrete contract.

A ridged base 5 results in excellent sealing performance.