The Angstadt Arms 5.5 inch free float hand guard is the perfect choice for your next pistol or short barrel rifle build. The unique design features a very slim profile (1.375 inch ID) that still allows for the installation of a sound suppressor of 1.40 inch in diameter and smaller to tuck inside of the handguard when used with an exact length 6 inch barrel. Works with 223/5.56 and 9mm. Handguard does not require timing and installs with a standard wrench. Features: Free float, 7-sided design that allows for 45 degree offset mounting options M-Lok mounting interface on 7 sides 2 QD swivel mounting points Continuous top Mil-Spec 1913 picatinny rail Compatible with both forged and billet upper receivers Compatible with both 223/5.56 and 9mm calibers Handguard does not require timing and installs with a standard wrench Mil-Spec hardcoat black anodize finish