The Model MDKP Exterior Wireless Keypad can transmit a unique signal for each 1-6 digit PIN code entered. It has a built-in radio transmitter with a 250-foot range in line-of-sight conditions. Access codes are programmed into the access controller or receiver, the maximum number of codes possible depends on the receiver model used.To operate the MDKP, a user simply enters a PIN followed by the # key, and the code is transmitted to the receiver for validation. Downlighting can be turned on by pressing the # key twice; it remains on for 30 seconds or until a code is sent. The MDKP can be mounted on either a wall or a gooseneck.Features•Internal antenna •1-6 digit PIN for each user •Long life lithium battery •Rugged cast aluminum housing •Built-in downlight •Power: 9-volt lithium battery •Codes: 1,000,000+ (MegaCode format) •RF frequency: 318 MHz •Dimensions: 4" W x 7" H x 3" DFor new installations you will need MGR 318Mhz Receiver for Wireless Capability.