Rotary Screw air compressors give you the ability to have consistent air flow with 100% duty. Piston air compressors need their down time, most with a max duty cycle of 70-75%. Even those claiming 100% typically tell you to allow 25-30% for leaks and other factors, leaving them with the 70-75% duty cycle that is common. Rotary screw air compressors are designed to run 24/7. Most also are enclosed providing compressed air, but with low noise.