This is a durable double lip seal, specifically manufactured to fit the Bosch crankshaft. An effective waterproof barrier for the Bosch right-hand crankshaft bearing. If fitted with the Mudstop bearing seal it makes a formidable barrier against water, mud or dust entering into the bearings of your expensive motor. 

 

Fits Bosch Gen 2 Active Line, Performance Line and Performance Line CX motors