THESE HIGH QUALITY MADE PISTONS ARE FOR STANDARD BORE FOR THESE ONAN ENGINES, B43, B48, P216, P218, P220, BORE 3.250 STANDARD BORE, THESE PISTONS ARE THE SAME WEIGHT AS THE OEM ONAN PISTON  COMPLETE GASKET SET & SEALS NOTE: THESE HIGH QUALITY MADE PISTON KITS, GASKETS & SEALS ARE NOT MADE IN TAIWAN OR CHINA SHIPS FROM USA WITH A TRACKING NUMBER