Compatible with NT65MA4(S)/ NT65MA4/ NT65MA4M/ N5008AC2 guns. Manufactured from durable PU material for resistance, performance, and durability. Designed to prevent damage to the driver and pistons Protects nail guns by absorbing piston driver firing shocks Specifications: PU Material The Superior Parts SP 877-170 is a generic replacement Piston Bumper that is compatible with Metabo/Hitachi, NV65AC / NV75AG / NV85AG / NV83A3 guns. Designed to protect nail guns from damage by absorbing piston driver firing shocks. Manufactured from durable PU material and precision machined for resistance, performance, and durability. A reliable replacement for OEM parts and highly recommended by Tradesman in the field.