Superior Parts SP 174055 Aftermarket O-Ring for Bostitch MCN150 & MCN250 (Piston Head Valve) - 2pcs/pack. Details Compatible with: Bostitch MCN250S Metal Connector Nailer MCN150 Metal Connector Nailer N75C Coil-Fed Pneumatic Sheathing Nailer N66C Coil-Fed Pneumatic Nailer MCN250 Metal Connector Nailer N75C-1 Type 0 Coil Sheathing/Siding Nailer N66C-1 (72400000) 15 Degrees Coil Siding Nailer DeWALT DW66C-1 (Type 0) 15 Deg Coi Side Nail DWMC150 (Type 1) 1.5 Metal Conec Nail Collapse the 10 compatible machines More Information Model# SP 174055 UPC 099461765771 WARNING California Proposition 65 Brand Superior Parts