These high quality exhaust studs are produced from corrosion resistant 321 stainless steel in 5/16 x 18 standard thread size (oversize available soon) and are a direct replacement for the Lycoming part number 31C12 stud.

These studs stop stud corrosion and rust out problems, stop expensive cylinder repair costs cause by broken studs, allow easy removal of exhaust systems for gasket replacement or inspection, and feature a safety wire hole to insure security of the exhaust stack on each cylinder. FAA approved for all Lycoming engines from 0-235 thru 0-540.