Square Wireless Doorbell and Telephone with Flash & Sound Alert System has 7 LED colors, 52 pieces of selectable ringtones, 4-level adjustable volume, IP 44 waterproof transmitter, over 600 feet operation range (open air), easy to add additional transmitter/signaler or receiver, low power consumption, and has a volume range of 30-110dB, 4 levels. Includes 1 doorbell receiver, 1 video/phone receiver and 2 wireless flashers. Includes doorbell battery 23A-12V. Receiver batteries not included (3 AA batteries required). Ideal product for the blind and hearing impaired. 1-year warranty. Wireless flashers measure 5" x 5". Doorbell and phone transmitter measure 3.50"L x 2.20W.