Chamberlain Wireless Doorbell Intercoms allow you to speak to guests at your door from anywhere in the home. These intercom systems run on batteries, and require no wires or power course. The Chamberlain system works up to a 1000 foot range, is expandable to additional units, and comes with a 1 year manufacture's warranty. 12"(H) x 8.5"(L) x 2" (W). Black Color (white shown in picture). Requires 4 AA batteries, not included.