2L X 9in circumference V-Belt. Polyurethane with Polyester tensile cords. V-Belts are superior to timing belts for power transmission as they use the “V” cross-section on the sides of the belt and pulley for engagement. The cogs (not teeth) allow the belt to bend around small diameter motor pulleys. This part is used on the .75” and 1.5” pulleys of the KINETIC kit.