Linear Multi-Code Keypad (420001) Weather-Resistant Keyless Entry Station Transmitter The item appears to be unused with no packaging or paper directions. All keys light up when tested with a battery, but I have no receiving device to do a full test. However, I accept returns for any reason within 30 days. I will refund the entire amount plus shipping. TWO AVAILABLE at this time. Directions: https://s3.niceforyou.support/products/MCS420001/216559_Rev-C_INSTR_INSTL_MC4200.pdf Literature: https://www.linearproaccess.com/wp-content/uploads/MULTI-CODE.pdf From the directions: "Your Keyless Entry System comes with a preset factory codes (2, 4, 6, 8, 10) for the radio code and (1, 2, 3, 4) for the 4 digit access code. We urge you to reprogram the unit with your own personal codes to prevent tampering." Remove the battery for at least one minute to reset the device to the factory settings. 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.