The standard 'O' Ring is prone to leaking and this seal is an improved solution for sealing on the selector shaft. Three per gearbox.
The seal is a tight fit and care is needed when fitting. Lubricate the seal well and press into the casting up to recessed face ensuring the seal is square to the face until it is very slightly proud of the surface. The recessed side of the seal should face into the casting with the marked face outwards to the closing plate.