BUTTERFLY DICE CUPS. Phoenix: Bill Gusias, 1980. Matching set of brown dice cups with padded bases, one straight, one gaffed. The gimmicked “butterfly” cup conceals two compartments. The operator switches from one to the other by pressing a sweet spot on the padded base of the cup and twisting to switch one set of dice for another before or after making an apparently fair roll. Height 4¾", mouth diameter 2¾". Very good working condition.