The Remington 870 Tactical Mount is used to attach accessories such as sights, scopes, flashlights or any other accessory with a picatinny/weaver base to your firearm. Specifications: Rail Length: 4.5 Inches; Rail Type: Weaver/Picatinny; Material: Aluminum; Applicable Firearm: Remington 870 Shotgun 12Ga. and similar firearms; Warranty; 1 Year Limited.