The Kynshot Hydraulic Recoil Buffer takes the place of the receiver extension tube, converting the AR-15 telescoping stock into a recoil-buffered stock assembly without further modification. The recoil buffer accepts mil-spec dimensioned buttstocks. The Kynshot Hydraulic Recoil Buffer is CNC machined from 6061-T6 aluminum and meets the stringent standards of military and law enforcement users. No gunsmithing is required for installation.