With a 37.7cc 4-stroke engine putting out 1.5 horsepower, this blower offers excellent power in an ergonomic you can feel a strong wind moving between your back and the blower body. The 4-stroke backpack blower has a much more mellow tone. It differs greatly from the high-RPM screaming 2-strokes Backpack design, super light weight 17.5lbs allowing you to move around freely. Engine displacement (cm³) 37.7 Output (hp) 1.5 Dry Weight (lbs) 17.5 Fuel tank capacity (l) 0.67 Air Volume (CFM) 580 Noise level 98dba.