Echo PB-770H Backpack BlowerThe PB 770 features an ECHO exclusive vented back pad for user comfort in hot weather, a 63. 3cc Power Boost Tornado engine that provides category best power, an easy to reach tube mount (PB 770T) or hip mounted (PB 770H) throttle with cruise control, a side mounted heavy duty, dual stage air filter for longer lasting engine, the Posi Loc system for a secure pipe connection, padded backrest and shoulder straps for operator comfort, and a leaf guard.