SEAPHY 1 Push Button + 1 Door Wireless Doorbell Operating at 1000ft / 300m Range with 52 Chime Tones, Black It contains 1 door chime (Receiver) and 1 waterproof push button (transmitter). 1000 feet / 300 meters operating range at most in open area, suitable for outdoor use. Pretty easy to install with screws or double-face adhensive tapes. Moedern design in classic black, nicely applied to home, office buildings, hotels, factories. Over 50 ring tones available, adjustable volume suits various senarios.