Tuff Stuff #80DC Dull Chrome Non Electric Doorbell Door Viewer, featuring a Chime Door Viewer that has a 4-3/4"H X 3" Wide Outside Plate, a 6" H X 3-1/8" Wide Inside Face Plate, a 180 Degree Lens Angle. This one way door viewer has a two note mechanical audible door chime, it requires No Wiring No Batteries and No Electricity.