5VX840 HC Molded Notch Belt, 5VX Section, 5/8″. V-belts, also called fan belts in automotive applications, link two or more rotating shafts to transmit power in a drive system. The trapezoidal shape of the belt’s cross section wedges into the groove of a similarly shaped sheave or pulley to provide traction and alignment. This wedging action increases as the load increases, providing higher torque transmission and minimal slippage. V-belts are standard for belt-driven power transmission and can be used in single- or multi-belt systems for increased carrying power.