Built in 5881ENH unlimited zone wireless receiver. The sounder beeps to help identify security system status. Easy to read with large characters and simplified descriptions. Fully compatible with all 5800 wireless devices including bidirectional devices(Not compatible with 5839). Comfortable soft-touch keys labeled with simple commands are illuminated for nighttime visibility. Four larger function keys can be programmed for one touch operation and are accessible even when the door is closed. Sleek, white design blends with any décor. Contoured, removable door lets customers customize the keypad for the look they want.