All backpack units are equipped with variable speed cruise control throttles and extra-wide shoulder straps and a contoured, air-forced, cushioned back pad that keeps users cool in the field. RedMax backpack blowers use only commercial-grade engines with large 2-stage air filters for long service life. Most models include our patented Strato-Charged engine technology. Backpack blowers are also equipped with wide-sweep elbow rotation for full operator mobility and maneuverability, even in cold weather. Commercial models are equipped with Free Flow Air Net, which reduces air intake blockage providing maximum blowing performance.