(4 Pack) Remington O-Ring Replacement Barrel Seals [OEM Graphite Coated] (Model 1100 12 GA, 11-87 12 Gauge) Replacement o-ring for Remington 1100, 11-87 12 Gauge Highest grade synthetic rubber o-rings with graphite coating replace old, worn, or cracked orings to provide a proper seal and restore gas system reliability. This is the same material used by Remington when your firearm left the factory. Used to resolve blow back issues with 12 gauge gas ports for Remington 1100 & 11-87 shotguns Material has high temperature, compression, and operational tolerances. Up to 316 C (600 F) and down to -54 C (-65 F) Manufactured and Warrantied by Captain O-Ring LLC