Dayco Polyrib Belt Double Sided - Dayco's extensive line of Poly Rib serpentine belts are engineered for high mileage even against the demanding drives found in modern vehicles. As the manufacturer of the first original equipment multi-ribbed v-ribbed belt, Dayco's commitment to automotive product excellence and innovation is unwavering.The Dayco Poly Rib W Profile accessory belt is the most innovative advancement in serpentine belt design in over 25 years. Developed through extensive laboratory and actual road mileage testing, this unique rib profile EPDM belt has been engineered to conform to high mileage, worn or misaligned drives and help eliminate noisy belt conditions.Constructed with aramid reinforced EPDM compounds, the Dayco W Poly Rib serpentine belt exceeds Original Equipment (OE) specifications.