The Linear ACT-21B MegaCode Single-Channel Block Coded Key Chain Remote (ACP00615) is a compact, one-button transmitter designed for Linear/Nortek MegaCode systems operating at 318 MHz. Built for everyday gate and garage door access, it provides dependable, single-channel control in a convenient key fob form factor. The ACT-21B uses Linear’s MegaCode format and is intended for use with compatible Linear MegaCode receivers and operators found in residential and commercial applications, making it a reliable replacement remote or add-on for existing MegaCode installations.
This block-coded version is factory coded for managed deployments, allowing property managers and integrators to assign and track transmitter IDs by block when enrolling users into access control systems. In many installations it can be added by placing the MegaCode receiver into learn mode and pressing the remote’s button; in managed, block-coded systems, enrollment is typically completed by entering the transmitter’s printed ID into the controller or software. The ACT-21B is compatible with Linear MegaCode receivers and operators (e.g., common Linear garage door and gate receivers that specify MegaCode at 318 MHz) and is not compatible with Linear Delta-3, Multi-Code, or other brands’ rolling-code technologies such as Security+ or Intellicode. A transmission indicator LED confirms button presses during programming and normal use.