ECHO CS-4920-18 Chain Saw 18" Rear Handle Professional 50.2cc EngineECHO CS 4920 18 Chain Saw 18" Rear Handle Professional 50. 2cc Engine ECHOs CS 4920 is the ideal mid range chainsaw made for versatility. From trimming limbs to felling trees to storm cleanup, its the lightest 50 cc chainsaw and has the power to cut through to get the work done. Features: 50. 2cc 2 stroke commercial grade engine Automatic, adjustable clutch driven oiler for reduced oil consumption Decompression valve for easy starting G Force Engine