ECHO PB-770H Leaf Blower Backpack Hip Mount Throttle 63.3cc EngineECHO PB 770H Leaf Blower Backpack Hip Mount Throttle 63. 3cc Engine Industry's best combination of air speed and air volume Features: 63. 3 cc professional grade, 2 stroke engine 756 CFM and 234 MPH Padded backrest and shoulder straps for comfort Exclusive vented back pad for user comfort in hot weather Variable speed hip mounted throttle with cruise control for convenience Side mounted, heavy duty, dual stage air filtration for long life