Steel, extra-power magazine spring replaces the factory spring and ensures that every shell is ready to be loaded when you need it. Orange aluminum follower lets you see at a glance when the magazine is empty. Drop-in installation requires no special tools and no gunsmithing. Instructions included. Only for 4 shot tube not 6. Mfg: Brownells SPECS: Steel magazine spring. Aluminum follower, orange. Fits Remington 870, 12 gauge.