Made in the usa the magpul str (storage/type restricted) is a drop-in replacement buttstock for ar15/m4 carbines using mil-spec sized receiver extension tubes.A storage-capable version of the ctr the str has improved cheek weld and two water resistant battery tubes on a compact reinforced polymer a-frame design.Firearm Type: AR-15Firearm Model: AR-15Material: PolymerFinish: BlackFeatures: Water Resistant Battery Storage TubesAdjustment Type: CollapsiblePositions: 6Length Of Pull: 10.90"-14.20"Tube Included: No