CMMG manufactures high quality parts and accessories for the AR-15 platform. This particular item is a replacement front sight assembly with gas block assembly. The front sight tower is designed to fit barrels what are .750" diameter with a gas journal approximately 2" long. This assembly requires pinning onto your barrel and the pins are sold separately. This unit should be installed by a gunsmith, or a competent AR-15 specialist only.

Specifications and Features:
CMMG Inc Replacement Part 55DA338
Front sight/gas block assembly
"F" Marked
.750" Barrel diameter
Sling loop
Bayonet lug
Phosphate
Black

Fits:
AR-15 barrels that are .750" diameter