The Spikes Tactical M4 Complete Stock Assembly is designed to equip the back end of an AR-15 lower receiver with superior components. This assembly includes a 6-position Mil-Spec Buffer Tube an M4 Collapsible Buttstock Receiver End Plate Castle Nut Buffer Spring and the ST-T2 Heavy Carbine Buffer.Features include:- Black finish- Comprehensive M4 stock kit- Includes ST-T2 Buffer Buffer Tube Buffer Spring Castle Nut End Plate- Compatible with AR RiflesFit: AR Rifles Description: Includes Buffer Buffer Tube Buffer Spring Castle Nut End Plate Model: ST-T2 Subcategory: Stocks & Buffer Tubes