... ) AS-568, PG, DIN, BS standard and non-standard Silicone O-Rings 2) Various colors available Features:1) AS-568, PG ... standard and non-standard Silicone O-rings 2) Various colors available, such as black, green, yellow ... , NBR, natural rubber, SBR, IR, IIR(butyl rubber), CR (neoprene), EPDM, SBR, AU, ACM, CO; wide range of materials are available ...