Recommended for 1-3 HP (horsepower) light-duty applications. Typically the best option for electric powered applications. For refrigerators, washing machines, pumps, stokers, woodworking machines, etc. Do it belts feature concave sidewalls to give the belt full-grip on the pulley sides. Polyester tensile cord. Rubber filled cords prevent separation of cores and rubber. Protective Fabric Jacket (made from special compounded rubber stock) for silent running, oil and heat-resistance. Meets Rubber Manufacturers Association standards for static conductivity.