CMMG Pistol Tube Assembly (55CA67D)

CMMG Mk4 Receiver Extension (55CA9D7)

Luth-AR 9MM Carbine Buffer Assembly, Mil-Spec Dia, Black 9MM-M-BAP

Battle Arms Development, Inc. 6 Position Buffer Tube, Mil-Spec Tube, Fits AR Rifles, Black AR15RE-MIL-6C

Luth-AR Mil-Spec Dia Carbine Buffer Tube Complete Assembly Fits AR-15 Rifles, with Buffer, Buffer Tube, & Spring, Black 223-M-BAP

SPIKE'S TACTICAL Pistol Buffer Tube (SLA500P)

LBE Unlimited AR15 Pistol Buffer Tube, Black PBT-BLK

CMC TRIGGERS AR15 8-Position Extended Buffer Tube Assembly Kit (83626)