Glossary

A2 Keyway: A common SFIC keyway profile used in commercial locking systems that determines which key blanks can enter the core.

A3 Keyway: A restricted SFIC keyway variation used to limit key duplication and increase security control.

A4 Keyway: A specialized SFIC keyway profile designed for high-security or proprietary lock systems.

Bitting: The series of cuts on a key that determines how it aligns with the pin stack inside a lock cylinder.

Bottom Pins: Pins inside the lock cylinder that come into direct contact with the key and determine the key’s specific cuts and alignment at the shear line.

Change Key: A key used to operate a lock in its normal working condition. It does not remove the core and is used by end users.

Control Key: A specialized key used to remove and install an SFIC core from its housing. It operates on a separate shear line from the change key.

Core (SFIC Core): The removable cylinder component of an SFIC lock system that contains the pins and key mechanism. It can be quickly swapped without removing the entire lock.

Cylinder: The assembled unit that contains the pins, springs, and plug inside the interchangeable core system.

Driver Pins: Pins located above the bottom pins that block rotation of the plug until the correct key aligns the shear line.

Fixed Tailpiece: A tailpiece permanently attached to the SFIC core, designed for specific lock applications where orientation and movement are standardized.

FSIC (Full Size Interchangeable Core): A larger version of an interchangeable core system used in some lock platforms. It is not compatible with SFIC systems.

Grand Master Key: A key that operates multiple master key systems within a larger hierarchy of locks, providing the highest level of access.

Housing: The part of the lock that holds the SFIC core. The housing remains installed in the door while the core can be removed and replaced.

Interchangeable Core (IC Core): A lock core that can be quickly removed and replaced using a control key, allowing fast rekeying without disassembling the lock.

Key Blank: An uncut key that is shaped to fit a specific keyway and can be cut into a working key for a lock system.

Key Control: A system that restricts unauthorized duplication of keys to maintain security within a lock system.

Keyed Alike System: A configuration where multiple locks are designed to operate using the same key for convenience.

Keyed Different System: A locking setup where each lock has its own unique key and cannot be opened by others in the system.

Keyway: The specific shape and configuration of a key slot that determines which key blanks can enter and operate the lock.

LFIC (Large Format Interchangeable Core): A larger interchangeable core system used in heavier-duty lock applications, not compatible with SFIC systems.

Loose Tailpiece: A tailpiece that is not permanently fixed to the core and rotates or adjusts during operation, allowing more flexibility in alignment.

Master Key: A key that operates multiple different locks within a system while each lock still has its own individual key.

Master Key System: A structured locking system that allows different levels of access using change keys, master keys, and grand master keys.

Mortise Cylinder: A type of lock cylinder installed inside a mortise lock body, commonly used in commercial doors and compatible with SFIC housings in some systems.

Operating key: The standard key that operates the lock during normal day-to-day use.

Pin Chamber: The internal cavity inside a lock cylinder where pin stacks are housed and interact with the key.

Pin Stack: The set of pins inside a lock cylinder that must align at the shear line to allow the plug to rotate.

Pin Tumbler System: A common lock mechanism that uses pins of varying lengths to prevent rotation without the correct key.

Pinning: The process of configuring or rearranging pins inside a core to match a specific key combination.

Plug: The rotating part of the cylinder where the key is inserted and turned to operate the lock.

Rekeying: The process of changing the internal pins of a lock core so it works with a new key while maintaining the same hardware.

Restricted Keyway System: A controlled keyway profile that limits who can legally duplicate keys for increased security.

SFIC (Small Format Interchangeable Core): A standardized removable lock core system used in commercial security applications that allows quick rekeying using a control key.

Shear Line: The precise line inside a lock where pins must align to allow the plug to rotate and the lock to operate.

Tailpiece: A metal component attached to the back of an SFIC core that connects the core to the locking mechanism inside the housing.

Top Pins: Pins located above the shear line that help prevent the plug from rotating without the correct key.