Maximize power to accessories with low stretch/non slip belt. Sierra serpentine belts are constructed using high strength synthetic cords that resist shock load failure and provide low stretch properties to assure uniform performance over the life of the belts. A special rubber compound is used in the compression section to transfer the load forces a smoothly and evenly to the cords. Precise engineered cogs are molded into the belt to improve flexibility and increase air flow while maintaining cord support. The added air circulation helps to keep the belt cool and prevent heat buildup that can damage and cause the belt to wear prematurely. The design of the rubber edges maintains a positive no-slip contact with pulley grooves for consistent energy transfer.