The "C" indicates small format IC core, which is the only core style Falcon products. The C987 will be provided less core unless -6, or -7 suffix is specified (6 or 7 pin core)
Example:...
Full Size Interchangeable Core, a large format cylinder core that can be removed from one housing and placed into another lock without removing or disassembling the lockset/door hardware.
(Small Format Interchangeable Core is a small format cylinder core which can be removed from one housing and placed into another lock without removing or disassembling the lockset/door hardware.
The Schlage B and BD cylinder suffixes designate less small format interchangeable core (SFIC) cylinder prep for the lock. Any SFIC, 6-pin or 7-pin, can be inserted into th...