Aftermarket Hitachi Framing Nailer Piston Driver. This is a generic replacement driver with o-ring for the Hitachi NR83AA framing gun. Aluminum is crimped into the UNI-LOK grooves of the shaft to prevent unscrewing. Hardened steel lock tite and micro-mechanically locked piston driver interface. Guaranteed never to unscrew.
Metabo HPT (Hitachi)