A great design in ergonomic cleaning comfort. The FlexFit harness moves in such a way to make wearing the vacuum on your back extra comfortable. This means less chance bumping into doorways and walls as you move around. The articulating harness lets you increase your range of motion, improve productivity, and reduce fatigue. The triangular shape of the body is designed to fit closer into the user's back making it feel less bulky and fatiguing. The die-cast aluminum tri-latch system assures air performance. Another feature is the exhaust is putting out aware from the user to keep you cooler while using the vac. Four level HEPA filtration is also a standard feature which captures 99.97% of particulates 0.3 microns or larger, improving IAQ (indoor air quality).