The ELK-950 is an RJ31/38X Telephone Jack containing solid state transient suppression designed to protect both the Telephone and Low Voltage AC Transformer inputs on an alarm control. It responds to power surges and transients in less than 1 nanosecond, automatically restoring after each surge within the specified ratings. The ELK-950 is compact and easy to install and features high quality, clearly labeled screw terminals, 8 pin modular phone connector, built-in tamper loop, and automatic shorting pins for cord removal. The ELK-950 is FCC Registered under part 68 and eliminates the need for a separate RJ31X telephone jack. The AC Transformer inputs may alternately be used for surge protecting data transmission wires such as a keypad or zone expansion bus, as long as any measurable voltage on the two data wires is less than 24 volts.