Our Garage Door Remote Receiver Keypad is a secure wireless keyless entry system that opens or closes your garage door without the use of a remote or key. The system can open the door using a dedicated 4-digit code programmed directly into the unit. Replacement for 877MAX G940EV-P2 878MAX 377LM 977LM 877LM 66LM CMXZDCG440 This garage door keypad uses the latest Security+ 2.0 rolling code technology to synchronise to your existing opener frequency, eliminating radio wave interference. Strictly tested using professional testing equipment. The garage door keypad has 3 channels connected to three openers, one keypad controls up to 3 motor units This wireless garage door keypad is compatible for 1993 garage door remotes with purple-yellow-red-orange-green learning buttons. Do not work for 200.57933 57943 57953 Series 100 CR1150 139.57943 139.57953 Keyless entry offers wireless installation and wireless programming. Large backlit buttons provide quick and easy entry in the dark. Protective cover protects against the elements. Provides one-touch closing function to easily close the garage door Convenient Design: Backlit buttons for quick and easy input in the dark. Protective cover protects against rain splashes. Product name:Garage Door Opener Keypad Item No.:877MAX Frequency:310/315/390Mhz Code:Rolling code Battery:Built-in battery 9V carbon battery Working voltage:3v Working current:less than equal 12mA Transmitting distance:100 metres (open) Operation : Same as the old remote control, need to be paired with the host computer Colour:As Shown Material:Plastic Package Contents: 1 x Remote Control 1 x Battery 2 x Screws/Nuts Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.