ZC-78P Vintage Arts & Crafts Single Push Button Switch Plate Field Pattern
Some early electric switches had only one button. Press once for on, press again for off. This is also a good switch plate cover for thin stem dimmer switches, or telephone and cable jacks.
Outside sizes might vary a tiny bit with the hand hammering technique, but it will not affect the precisely placed switch holes.
2 3/4" x 4 1/5"