Carper 390 keychain remote This is a GENIE brand Keychain remote, so how do I know if it's the right one for me? 1. Frequency: Check the back of your current remote to make sure it says one of these Genie brand names: Alliance, Norelco, Blue Max, Lift-A-Door, Pro Max, Hercules, Stealth, Excelerator, Python, Signature, Phantom Legacy, Medallion, and CodeDodger. 2. Dip Switches: Open the battery compartment on your old garage door remote and look to see how many dip switches (tiny switches in a row) it has. If your old remote has 9 OR 12 dip switches and is a genie brand, then it's a match for this remote. If you don't have your old garage door remote, you can also look to see how many dip switches are on the back of your garage door opener (the overhead unit in your garage). The number of dip switches on the back of the opener is the same as on the remote. Features and Specifications Key-chain size garage door opener transmitter with a built-in flashlight, key ring and 12V battery included Mini ""key chain"" size (2"" by 1"") automatic garage door opener remote Compatible with ALL Genie 390 MHZ frequency with dip switches (9 or 12) Key chain and convenient surface mount kit included Compatible with Genie remote transmitters models AT85, AT85P, MAT85, AT90, MAT90, CT90, LD12, AT95, AT285, AT290, LDT/GPT/GT90-1, 2, 3, 4 Also compatible with Lift-a-Door and Blue Max garage door opener systems