This piston is made in the USA from a high quality forging as are all pistons manufactured by Combustion Technologies. This piston is a domed high compression replacement for Continental O-520 series engines and weighs approximately 1195 grams. This piston utilizes aluminum forging alloy 4032, common to most aircraft pistons - Lycoming and Pratt & Whitney, and does not utilize an iron ring groove insert. This piston accepts standard Continental 5.250 bore ring set and piston pin.