This International Standard specifies the principal characteristics of grooved pulleys (for groove sections AJ, BJ, CJ and DJ), intended to take joined classical V-belts for industrial power transmission drives. NOTE 1 The effective width of a groove is regarded as the basic dimension of standardization for grooves and for the corresponding joined V-belts considered as a whole. NOTE 2 The pitch line position can only be given approximately. The approximate pitch diameter of a pulley can be calculated by the following formula: dp = de − 2be