1.LSB specially produce the o-ring,x-ring.rubber parts 2. Material: FFKM,NBR, HNBR,EPDM,SI,FKM(VITON)CR, ... ,PU oil seals , rubber flat washers, rubber Circles, Gaskets, engine parts and accessories,compression mold , etc. 4. Certification:ISO9002:2009, TS16949 ,NSF ... . Different sizes and color can be make on your requirement ,but o-ring's mold fee is free. industrial rubber oil ring ...