B-Square Remington 912 and 20 Gauge with Serial X/N, 870 Express 3.5-Inch Mag Shotgun Saddle Style Mount, Matte Black Finish Full-length Allows for proper eye relief Fits Remington 870 12/16/20Ga, 870 express Shotgun Saddle mount, constructed of Aircraft Aluminum Multiple cross slots provide eye relief adjustments No-Mar design will not scratch or mar shotguns