The Keystone Heddolf CRC390-3KB is a 3-button handheld transmitter engineered as a compatible replacement remote for Chamberlain, LiftMaster, and Sears Craftsman Security+ garage door openers that operate on 390 MHz rolling code. Designed to mirror the core functions of the original Security+ remotes, it can control up to three separate doors, gates, or receivers that use the 390 MHz Security+ platform, making it a practical replacement or add-on for residential or light commercial applications. Its Security+ rolling code technology changes the signal with every press to help deter code grabbing, aligning with the performance and security behavior buyers expect from the original LiftMaster/Chamberlain ecosystem.
Programming is quick and switch-free: use the opener’s Learn button (red/orange Security+ 390 MHz) and then press the desired button on the CRC390-3KB to sync—no DIP switches required. This compatible remote is intended specifically for 390 MHz Security+ systems with a red/orange Learn button and compatible external receivers; it will not work with purple Learn button 315 MHz Security+ models, yellow Learn button Security+ 2.0 systems, or older fixed-code/dip-switch equipment. Typical use cases include replacing lost Chamberlain/LiftMaster/Sears Craftsman 390 MHz Security+ remotes (such as the 973LM series), adding an extra transmitter for additional users, or operating a gate equipped with a 390 MHz Security+ receiver. Frequency: 390 MHz RF. Always program and test the remote from a safe location and verify your opener’s Learn button color and radio system before purchase to ensure proper compatibility.