Remington 870 Magazine Cap w/Detents 12ga. This black finished steel magazine cap will fit Remington Model 870 12 gauge shotguns and is a factory OEM part. The cap is designed for use with a detented magazine tube and features inner detent ridges. A hole in the top allows for the use of a sling swivel eyelet. Made to the same factory specifications, materials and standards as the parts in your firearm.