This Liftmaster 971LM is equivalent to the Sears Craftsman 139 model number listed above. The back of your garage door opener motor should have a SMART button that lights up an Orange/Amber Color LED Light to code the remote. This is a Security Plus remote that is a 1 channel/button transmitter, compatible with models manufactured from 1997- present. It operates on a 390 MHz Frequency, and has over 100 billion codes with code rotating technology (Security+). A visor clip and Lithium battery (5 years life with normal use) are included, along with instructions. Compatible with ALL Security+ systems, including Chamberlain, Sears, Craftsman and Raynor code rolling residential openers. The corresonding wireless keypad is the 976LM wireless keypad for Security Plus 390MHz garage door openers.