polyurethane seal Good sealing, water resistance, oil resistance OEM,ODM available ISO9001,SGS,ROHS Lead ... ,POM,PUR,PVC,PPTV,HIPS,ABS,EPE,EVA etc.,with hardness between 30-90 shore A.2)performance:Good ... Bolt O-RingFront Main SealRear Main Seal (The rear main seal may change color with out notice)Crank Angle Sensor O- ... modify your enigine for race tolerances and performance. polyurethane oil seal ring