Features: 1.Application: This cylinder piston crankshaft assembly is specially designed for STIHL 029 039 MS290 MS310 390 Chainsaw Crankshaft. 2.Characteristic: The cylinder piston crankshaft has the advantages of low wear, low noise, low expansion coefficient, good heat dissipation and low fuel consumption 3.Durable Material: The piston cylinder kit is made of steel and iron materials, not easy to wear, and has the characteristics of high strength, rust resistance and aging resistance. 4.Stable Performance: High performance chainsaw cylinder crankshaft assembly, not easy to damage, can effectively extend the service life of your machine. 5.Nice Replacement: The manufacturing conforms to the standard specification, engine motor cylinder crankshaft is a direct replacement for the old or broken one. Specification: Item Type: Cylinder Crankshaft Assembly Material: Steel + Iron Cylinder Hole Diameter: Approx. 49mm / 1.93in Application: Fit for STIHL 029 039 MS290 MS310 390 Chainsaw Crankshaft