Update your semi with a quiet belt that generates stable electricity, with the Dayco 1.1" x 70.08" Poly Rib® Heavy Duty Serpentine Belt that ensures you're Ready for the Road Ahead™. To supply power to a vehicle's accessories, this replacement belt works with multiple tight pulleys and the alternator to convert mechanical energy into electrical power. Fashioned with modern EDPM rubber materials to reduce how often a belt should be changed. FleetPride is your First Click in Heavy Duty®.