From the Manufacturer
The wireless keyless entry pad from Chamberlain allows secure, coded access to your garage without a remote control or keys, just by entering the private 4-digit security code you determine. Just like the rolling code in your remote control, the keyless entry transmits a new code with every use, one of over 100 billion, never to be repeated. Also has the ability to be programmed for a temporary password. This model mounts easily on the garage door jamb without any wiring or hardware required. Illuminated for nighttime use. Only for use with Chamberlain Security+ garage door openers.
"CHAMBERLAIN" KEYLESS ENTRY PAD
Rolling code security technology
Temporary password options
Includes battery and mounting hardware
For Chamberlain security and GDOs only
Replacement battery: 9 volt Ace#: 32116