Compatible with: Hitachi NT65MA2 15-Gauge Angled Finish Nailer NT65MA3 2-1/2" 15-Gauge Angled Finish Nailer NT65MA4(S) Finish Nailer NT65MA4 Finish Nailer Superior Parts SP 882-685 Aftermarket Piston O-Ring Compatible With Hitachi NT65MA4, NT65MA4, NT65MA2 Nailers Replaces OEM 882-685 - 2pcs/pack.