The Wireless Commercial Keypad comes with one 9V Lithium battery, instructions, and two keys. A wireless signal is transmitted when a valid 4-digit PIN and the # key is pressed. A long tone will sound. The keypad back light will illuminate for 15 seconds when any key is pressed. If an invalid PIN or partial PIN is accidentally entered, an error tone will sound. The Wireless Commercial Keypad is compatible with the brands of commercial door and gate operators listed in the table below.