Lee Electric PI1640 White 16V Plug In Type Class 2 Transformer With 40VA, specially made with a sleek design for heavy duty signaling. Caution to reduce the risk of electrical shock, disconnect power to the receptacle before installing or removing the unit. When removing receptacle cover screw, the cover may fall across plug pins or receptacle may become displaced. Use only with duplex receptacle having center screw and secure unit in place by receptacle cover screw.