Schlage Commercial C503-118 Full Size Interchangeable Core Cap

The C503-118 is the cap for a Schlage full size interchangeable core (FSIC). It is the small end component that closes off the core body, not a complete core and not a cylinder. If you are rebuilding or re-keying an existing FSIC and the cap is damaged, lost, or you need a spare on the bench, this is the replacement piece. It does not include a core, pins, springs, or a control key.

No. The C503-118 is a full size interchangeable core cap, so it is sized for Schlage FSIC cores. Small format (SFIC, the Best-style 6 and 7 pin format) cores use a different body and a different cap, so this part will not serve there. Confirm the core in hand is full size before ordering.

Just a component. Ordering the C503-118 gets you the cap alone. If you need a working keyed core for a lock, you need a full size interchangeable core ordered to your keyway and keying, plus a control key to remove and install it. The cap is a service part for a core you already have.

If you service Schlage full size interchangeable cores, yes, it is worth a few on the shelf. Caps get dropped, deformed, or lost during teardown, and a core without its cap cannot be reassembled and put back in service. Keeping a couple of C503-118 caps in the kit avoids pulling a whole new core off the shelf over a lost part.

One. The C503-118 is a single model with no finish, size, or handing options to specify, so there is nothing to select on the order beyond quantity. That makes it straightforward for a property manager or MRO buyer standardizing Schlage FSIC hardware across a facility.