The Allstar 108794 Single Button Classic Remote 9921T is a one-channel handheld transmitter designed to operate compatible Allstar and Allister garage door openers and gate operators that use the Classic 318 MHz dip-switch radio system. Often referenced simply as the Allstar 9921T, this replacement remote provides straightforward, reliable control for residential or light commercial access applications where fixed-code transmitters are required.
Operating at 318 MHz, the 9921T uses a 9-position trinary dip-switch code (+, 0, −), offering 19,683 possible code combinations for dependable interference resistance within the Classic series ecosystem. Programming is simple: open the case and set the nine internal switches to match the code switches on the opener’s receiver or an existing working transmitter. This model is intended for Classic fixed-code systems and is not compatible with Allstar MVP/learn-button or rolling-code technologies, nor with brands using other frequencies such as Multi-Code 300 MHz, LiftMaster/Chamberlain Security+, or Genie Intellicode. Power is supplied by a 9-volt battery. For safe operation, confirm compatibility with your opener’s radio and test door or gate safety sensors after programming.