This UTG AR-15 Carbine Free Float Quad Rail Handguard is 7 inch long Mil-Spec Picatinny Rail Systems and replaces your original upper and lower AR hand guards. This utg free float carbine quad rail is CNC machined from solid aircraft grade aluminum and hard coat anodized for maximum strength with four mil-spec Picatinny rails for versatile accessory applications like red dot sights, scopes, flashlights, pistol grips, and lasers. Solid locking features for most secure fit ventilation slots on the Quad-Rail allow maximum heat dissipation which keeps the barrel cooler. Ultimate tactical solution to enhance accuracy under toughest environments. Fits CAR length 16 inch barrel model 4,15,16 Colt, Bushmaster DPMS and most variants. Hard anodized finish for wear resistance. 12 Rubber rail guards included for great comfort and protection. Mil-Spec Forearm. UTG Limited lifetime warranty. Fits Carbine Length Model 4/15/16 rifles.