Vincent Piston STD ~ 83,98mm 1000cc With Gudgeon Pin - DM: 7/8", Circlips and Piston Rings 9:1 Compression, Compression Hight: 32mm Piston Clearance 0.12mm or 45thou, cast Parts Suitable for Use Soleley or Principally With Spark-Ign. Int. Combustion Piston Engines domed with valve pockets Made in EnglandPlease look at ALL Pictures