The Stihl Piston Cylinder Diameter 44 mm (code 1143-020-1207) is an original spare part for Stihl MS 251 chainsaws. Includes piston Diameter 44 mm, compression ring Diameter 44x1.2 mm, piston pin 10x8x27.88, circlip 10, screw for plastic IS-D5.3x43. MN