The Mossberg 500 A Forearm features a lower accessory rail system for the Mossberg 500 A. It is used to attach accessories such as a bipod, flashlight, foregrip or laser to your firearm. Two additional side rails allow you to attach more accessories. Specifications: Rail Length: 9 Inches x 2 Inches x 2.4 Inches; Rail Type: Weaver/Picatinny; Material: Aluminum; Applicable Firearm: Mossberg 500 A, and similar firearms; Warranty: 1 Year Limited.