A serpentine belt, sometimes referred to as poly-v, multi-vee, or multi-rib belt, is a single, flat, continuous belt that drives multiple peripheral devices like A/C compressor, air pump, alternator, power steering pump, water pump, and some other components. It similar to the toothed belts used as timing belts but with lengthwise V-shaped ribs rather than transverse cogs.
Serpentine Belt 
