Fluorosilicone Extractor O-ring High Temp Blue (M25988) -  Per each

Can be used for enhanced extractor tension on AR15, M16, M4, and AR10 type rifles. These o-rings are mil-spec M25998 MIL-R-25988 high temp fluorosilicone material. Same application as Armalite EB0065, but higher temp-rating.