The Model 420001 Wireless Keypad is a weather-resistant keyless entry station transmitter. Entering a programmable 4-digit access code sends the programmable radio code to the receiver to activate the door or gate operator. The transmitter is powered by a 9-volt battery, has a test/operate indicator, and keys that light during use. When the battery gets low, the keypad will blink during use to indicate that the battery needs changing. The transmitter is Multi-Code format providing 1,024 possible radio codes. The transmitter will only activate receivers set with the same code programmed into the keypad.