Superior Parts SP 888-033 Aftermarket Piston Driver for Hitachi NV90AG. Aluminum is crimped into the UNI-LOK grooves of the shaft to prevent unscrewing. The UNI-LOK piston driver is designed to ensure that our Piston Driver Assembly remains securely fastened and guaranteed to never unscrew. Features: This part is compatible with following Hitachi model numbers: Details This part is compatible with following Hitachi model numbers: NV90AG Coil Nailer More Information Model# SP 888-033 UPC 099461760646 WARNING California Proposition 65 Brand Superior Parts