Complex sentence: A propane burnisher is a type of rotary floor buffing (polishing) device that is powered by propane, and is designed to rotate in speeds in excess of 1200-1800 RPM.
Split into simpler sentences: A propane burnisher is a type of rotary floor burnisher, a floor buffing (polishing) device, that is powered by propane. It is designed to rotate in speeds in excess of 1200-1800 RPM.