Liftmaster 365LM-2 Plug-in Security Plus Radio Receiver Kit 315MHz for Garage Door Opener - Wireless Remote Control System for Home Security & Automation

We have three 1979 Sears garage door openers in use in our family, and the remotes are no longer available. Chamberlian/Liftmaster made them for Sears under the "139" model prefix. The remotes are discontinued because I believe they are on a frequency that has since become restricted. Rather than throw out something that works perfectly fine, this was the solution. This is easily wired into the back of the opener and makes it now have a 'learn" button.With that, you can program the two included remotes and there you go, you have working remotes again. Liftmaster will tell you to scrap it if it's older than 1982 because they do not have safety sensors. However, this kit works just fine and not only got us working remotes, it converts the machine to "rolling code" technology, updating the security of it.Good value for the money and an easy install.