NuTone BK147LWH Recessed Chime with One Lighted Pushbutton and One Standard Transformer Basic white textured louvered faceplate covers the chime mechanism that is recessed into the wall for an installation that blends with builder finishing techniques For use with one or two entrances; two-note chime for front door, separate one-note tone for second door so no guest will be missed Order as standard pack of 24 to assist with your planning and still retain that economical edge Chime wires to a 16-volt transformer so you are assured of uninterrupted service and are never dependent upon batteries (transformer C905, included) One lighted rectangular shaped pushbutton with non-stick action included so you have one less thing to buy and the convenience of a complete Package