Precisely Fit and Easy Installation :Specifically designed for 135, 135E, 140, and 140E chainsaws (model 578257101), this drum set ensures perfect compatibility with OEM parts for direct replacement and quick repair without modifications. Metal Construction : Made from quality steel/manganese steel with precisely heat , this 6tooth passive gear resists deformation and impacts, ideal for highly speed chainsaw operations in demanding logging conditions. Complete Repair set: Passive gear, shoes, springs, needle bearings, drive shafts, and seals for a , ensuring smoothly power transmission and reduced slippage during operate. Enhanced Features : Features surfaces for outdoor durability, evenly tensioned springs for responsive engagement, and precisely engineered tolerances for low noise/vibrations operate. Versatile Forestry Application : A wear part suitable for home trimming, logging, and clearing, with modulars components available for individual replacement to reduce maintenance costs., Manufacturer: CUNZJIA