DoubleStar is a high quality manufacturer of AR-15 parts and accessories. This particular part is a receiver extension/buffer tub for an AR-15 pistol build. It includes the carbine length spring and buffer, and features a 1.25" ambidextrous sling mount.
Specifications and Features:
AR-15 Receiver Extension/Pistol buffer tube assembly
1.25" Ambidextrous sling mount
Billet Machined Gusset
Foam OverTube (cut to length)
Carbine buffer and spring included