This multi-ribbed belt transmits drive from the engine crankshaft pulley to the alternator rotor. It sits in the accessory drive system, routing around the alternator pulley and any idler or tensioner pulleys in the same circuit. The six-rib profile mates with the corresponding grooves on each pulley to prevent slip under load. A worn belt produces a squeal under acceleration or at high electrical load, and can lead to undercharging of the battery. On replacement, verify the belt routing matches the original path and that the tensioner is within its working range.