The key-in-knob and mortice cylinders shown here are a mix of Schlage “C” and Schlage Primus XP. Locks utilizing Schlage’s “C” keyway are by far the most common lock that I rekey. Primus XP high security keys are compatible with “C” keyway so I can eaily incorporate high security cylinders into an existing keyed alike group or master key system.
In this case all of the cylinders were keyed alike. The high security cylinders were installed on doors where a higher level of security was required.