Constructed of Military Grade DuPont Extreme Temperature Glass Reinforced Polymer. Rail locations are at 90 degree increments around forend. Picatinny Rails allow for easy installation of all of your favorite accessories. Very tough, yet extremely lightweight. Features include tactical shotgun Picatinny Rail package, one left 2" Picatinny Rail, one right 2" Picatinny Rail, one 2" bottom Picatinny Rail and three blank inserts for when rails are not in use. Includes Mounting Hardware and Adapter Kit which allows installation to, Mossberg* 500/535/590/835, 12 Gauge, Remington 870, 12 Gauge and Winchester 1200/1300, 12 Gauge. The forend included in this package is only compatible to Mossberg Shotguns with a removable forend, any Mossberg Shotgun newer than 2006 should be checked to insure that it has a removable forend.