TACO Trans Atlantic DCV01 Polished Brass US3 Door Viewer And Non Electric Chime Combination, Chime Door Viewer 4-3/4"H X 3" Wide Outside Plate, 6" H X 3-1/8" Wide Inside Face Plate, 180 Degree Lens Angle, One Way Door Viewer, Two Note Mechanical Audible Door Chime, No Wiring No Batteries No Electricity, The non-electric chime easily fits almost all doors, and saves worrying about power problems. The 180 degree viewer aids security. There are frames for apartment number and resident's name.