419pcs O-Ring Assortment *O ring: NBR *Case: ABS *Stretchy, durable, *temperature holding -20 degree to 80 degree 419pcs O-Ring Assortment1. Materials: NBR,also can be NR, HNBR, MVQ, ACM, FLS, CR, SBR, SI, BR, IR, EPDM, IIR, PU,E/A, ECO, CSM, VITON, FKM, FPM, etc.2. Characteristics: oil proof, aging resistant, heat resistant, wear resistant, chemical resistant, anti-corrosion, etc. 3. Hardness: ...