Stores up to 1000 telephone numbers | EEPROM Memory Chip | Full duplex communication | 4-digit entry codes (up to 1000) | 5-digit entry codes (up to 6) | 15 area codes | 16VAC, 20VA (250ma) power transformer provided | Ringer equivalence: 0.0 A | Jack type: RJ11C or W | FCC (US): DUF6VT-12874-OT-0 | DOC (CAN): 1736 4507 A | Complies with UL 294; ETL Listed | Surface mount dimensions: 7.375″H x 11″W x 6.375″D | Programmable directory codes (1-4 digits) | 10 and 11-digit dialing capability | Two special inputs can be programmed for relay activation