The Model 1835 is an ideal telephone entry system suited for apartment and gated community applications as well as office buildings and industrial sites. Each 1830 Series unit allows Voice and Data connection over Cellular, Internet or a POTS (Plain Old Telephone Service) connection.The single-line LCD display features big 1/2-inch characters for easy viewing and your personalized message scrolls across the screen from right to left when the system is not in use. Our unique "One Touch" CALL button makes this system one of the easiest to use on the market today! The built-in electronic directory, easy to use Remote Account Manager programming software, card reader interface and expandability options make this unit an ideal choice for those applications with a large number of system users and entry locations. With Tracker expansion boards, up to 48 wired card readers (or 24 wirelessly) can be interfaced with the 1835 to provide access control.Additionally, our elevator control module restricts which floors a guest or system users have access to, making it an ideal system for high rise buildings. For additional security, the 1835 allows you to monitor activity AS IT HAPPENS on your computer display and with our anti-pass back memory, you can enable a TRUE anti-pass back system in one of three different configurations; passive, active and trap.