A series of driven rolls for separating blow-molded products from segments of flash material in a string of products formed in a synthetic resin continuous molding machine. A first pair of rolls receives a string of products joined by flashes as the products are removed from the dies of a blow-molding apparatus. At least one of the rolls in the first pair of rolls is driven at a first rotational speed. An intermediate pair of rolls receives the string of products and flashes from the first pair of rolls, and the intermediate rolls are driven at a speed faster than the first rotational speed to stretch the string of products and thereby separate the flashing segments from the products. A pair of last rolls is spaced by an interval from the pair of intermediate rolls. The interval between the intermediate rolls and the last rolls is adjusted such that the products and the flashes can be sorted by length. The longer of the products and flashes are advanced through the pair of last rolls, whereas the shorter of the products and flashes drop through the interval between the rolls, thereby sorting the blow-molded products from the flash segments. Preferably, the distance between the pairs of rolls is adjustable to accommodate strings of products and flash segments of various configurations. Additionally, the last rolls are preferably driven at a speed faster than the intermediate pair of rolls to facilitate cutting and to quicken the advancement of material by the last rolls.