Manufactured from 6061 aluminum and hard coat anodized for durability, these 2-piece handguards are a drop-in replacement upgrade over factory plastic handguards. Offering a quartet of M1913 Picatinny accessory rails with laser engraved T-marks, installation follows the same procedure used for the original polymer handguards. No gunsmithing or permanent gun alterations are necessary. Handguards are compatible with direct gas and most gas piston operating systems for added versatility. Notes: Barrel nut not included FeaturesNo gunsmith installation. Simply install like factory plastic units.MIL-STD 1913 rails.Solid lock-up. T-marked for accessory location.Constructed of 6061 hard coat anodized for a lifetime of service.Grenade launcher or shotgun compatible with lower section removed.Compatible with most gas piston operating systems, Except for those produced by Osprey Defense.