NcStar AR-15 Quad Rail system is designed to replace your standard AR-15 hand-guards installing in minutes with no gun smithing or modifications required. The removable weaver style rails are customizable so you can attach forward grips, flashlights, lasers, or any other type of rail mounted accessories. It is constructed of hard anodized aluminum to prevent corrosion for lasting durability.This model is 6.7" long and has a black anodized finish. Features: NcSTAR's 3rd generation MAR4S, 223/5.56 carbine length quad rail handguard The 3rd Gen MAR4S is now lighter and has a slimmer profile than earlier models Fits onto carbine length gas system using the GI handguard cap and delta ring The solid quad rail provides the steady platform attaching - optics, lasers, flashlights, vertical grip, bipod, and other accessories Large ventilation holes to help keep the barrel cool Very easy to install with four Allen head screws and the provided mounting tool No gunsmithing required, drop-in fit Laser engraved rail markings (white)