This cylinder is unusual because it is an IC core cylinder but is keyed or pinned more like a conventional cylinder.
6 pin c or e keyway - works with many Kaba Ilco Simplex type locks. These are sent as they come from the factory. Comes number one bitted with 2 regular uncut keys (you'll need to cut them) and in addition, one uncut control key (you'll need to cut this also). The 2 regular keys will be used like any key to unlock the lock and the other key, the
control key is used to extract the cylinder easilly if you want to chane it with another.