Abstract: In an exercise machine having at least one cable, lift shaft and weight stack, the weight stack including a plurality of weights extending vertically from lowermost weights to uppermost weights, the weights and lift shaft having corresponding apertures to permit the selection of weights lifted by a lifting bar, a restricted range weight selector system includes a plurality of differently-sized weight selector pins and the apertures in the weights and/or lift shaft being progressively sized, such that the range of weights that may be selected by a user is restricted depending on the size of selector pin in the user's possession.