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.The Model 420001 is compatible with 300 MHz Multi-Code receivers and Model 109950 and 302850 receivers.FeaturesCompatible with 300 MHz Multi-Code receivers4-digit access codeBacklit keysEasy access to batteryPower: 9-volt batteryCodes: 1,024 (set by dip switches)RF frequency: 300 MHzDimensions: 2.75" W x 6.25" H x 1" D