DoubleStar's 16" HBAR Flattop Upper starts with their 5.56 chambered 16" HBAR barrel made from 4140 chrome moly steel utilizing the carbine length gas system. This match barrel is attached to their flattop upper with their carbine handguards. The upper is fully assembled with charging handle and semi-auto bolt carrier group. All parts are completely made in the USA.

Specifcations and Features:
Caliber: 5.56x45 NATO
Twist Rate: 1:9 Right Hand
Barrel Length: 16"
Barrel Type: Heavy Barrel
Barrel Material: 4150 Steel
Barrel Features: Black Nitride Finish, M4 Feed Ramps
Gas System: Carbine
Upper Receiver Type: Flattop
Upper Receiver Material: Forged Aircraft 7075 T6 Aluminum
Upper Receiver Features: "T"-Marks, Brass Deflector, Forward Assist, M4 Feedramps
Upper Receiver Coating: Anodized to Mil-Spec
Sight / Gas Block: "F" Marked Front Sight
Muzzle Device: A-2 Flash Hider
Handguard: Carbine Handguard
Includes Charging Handle and BCG
Made in the USA

Fits:

AR-15 lower receivers