... . Y-Ring.U-Ring., Oil Seal,PU oil seals , rubber flat washers, rubber Circles, Gaskets, engine parts and accessories,compression mold , etc ... ,etc.7. Standard:AS568,DIN3771,JIS B2401,ISO3601,BS1806.8. accept sample or product drawing on your size9. Different sizes and ... ,but o-ring's mold fee is free. KTW standard rubber seal