Working principles Interchangeable core locks are incredibly convenient because of their simplicity. When it comes time to change locks, you must turn the control key in the opposite direction. This saves you the time and money of having to replace your locks.


Interchangeable core locks offer convenience and flexibility. This type of lock features figure-eight-shaped essential cores that can be removed and inserted easily. They can be rekeyed without the assistance of a professional locksmith. An interchangeable core lock saves time and money when rekeying door locks.

Interchangeable core locks can be found in a variety of sizes. Large format and Small format interchangeable cores are available, and both are widely used. The Small Format Interchangeable Core (SFIC) is a popular choice for residential and commercial applications. It also features an easy-to-maintain design. Simply replace the core, and you’re ready to rekey.

Another reason to choose an SFIC lock is security. The SFIC lock has two shear lines, which makes it difficult for an attacker to break into the lock. An attacker would need to cut all of the pins in both directions to open the lock. Because each shear line is unique, an attacker wouldn’t have any way to guess the exact location of each cut, so it’s more difficult for an attacker to break into a lock with an SFIC lock.

Moreover, a rekeyable door lock with an interchangeable core makes it easy to change the lock and distribute keys to crucial holders. This saves time and money. The traditional rekeying of locks takes a long time and requires a technician to take the lock apart. Moreover, rekeying several hundred locks can cost upwards of $20,000, which is expensive for most businesses.

Many commercial spaces use interchangeable core locks for easy management. They are also easy to replace and rekey with a control key. This saves a great deal of time and effort. This makes them a valuable tool for businesses, commercial properties, and locksmiths.


An LFIC or Large Format Interchangeable Core is a door lock with an interchangeable cylinder. These locks are designed to be rekeyable by non-locksmiths without specialized tools or lock knowledge. They are available in various sizes, keyway configurations, and security levels. They are also available with bore auxiliary deadlatches for added security. These locks are UL437 listed.

SFIC (Small Format Interchangeable Core) lock cylinders are more universal than LFIC (Large Format Interchangeable Core). SFIC locks have a lower profile than those with larger cores. This feature allows building owners to use the same key for multiple locks without rekeying the entire lock system.

Interchangeable cores are an essential part of commercial multi-site security. Without them, it would be very difficult to keep security up to date and keep facilities safe. Changing locks at a large facility would be time-consuming, expensive, and logistically unworkable. With IC cores, facility managers can easily update security after a key is lost or misplaced. Changing a lock with an IC core is easy and painless and does not require locksmith assistance.

Until the early 2000s, LFICs were not top-loading. To pin a core, locksmiths had to remove a plug from the housing and load it from the bottom. However, in 2002, Yale designed their cores so that they could be loaded from the top through a capping strip. However, pinning can be tricky, and a locksmith may need to disassemble the lock to pin the core. Also, the top pins might get stuck in the groove and lock up the core. To prevent this from happening, a shim may be added to the lock to protect the pins from locking up.

LFIC door locks have the same benefits as SFIC door locks but can be easier to rekey. An LFIC lock is easier to rekey because it does not require the disassembly of the cylinder. This makes it easier for laypersons to rekey the lock.

UL Listed

Interchangeable core door locks provide a variety of security options. These locks can be used in single-point or multipoint applications. In addition to their multiple uses, they are available in various configurations, from preassembled to swinging. They can be used on doors with up to a 3-hour fire rating.

An Interchangeable Core was first developed to solve post-installation critical control problems. It allowed for entire buildings to be pinned both in the shop and the field, with minimal external key duplication. Most major hardware manufacturers later adopted the Interchangeable Core. They are available in several sizes and have their own locking lug and pinning. They have become a standard in the industry and are available from all domestic manufacturers.


Rekeying door locks is a simple process that can save you time and money. Using a lock with a user-rekeyable core allows you to change the key up to nine times without needing to take the lock apart. You can rekey your door lock with just a few clicks. Rekeying your door lock also saves space and money because you won’t have to store the replacement core and keys. Rekeying is also much faster than replacing a lock with a traditional one.

Changing locks is an inevitable part of running a business. It becomes especially troublesome when you have more than one location. However, an effective key control system can save time and money without compromising security. The type of key control system you use will depend on the size and industry of your business. However, rekeyable interchangeable core door locks provide great flexibility and can be integrated with your current key system.

Another way to rekey a door lock is to remove the cylinder. If you aren’t familiar with rekeying, you can learn the process here. You can use an interchangeable core lock if you need to change the key in a hurry. It is easy to rekey a lock using a user-rekeyable key. If you have a lost or stolen key, you can use a rekeyed lock to replace it.

Interchangeable-core door locks are more accessible to change than traditional locks. They contain a figure eight-shaped cylinder that can be easily removed from the lock hardware. You can do it yourself by using a control key or paying someone else to do it for you. It’s a simple process and can save you money in the long run.

If you have many keys and frequently change them, an interchangeable-core door lock may be the right choice for you. They have two main advantages: ease of rekeying and cost-effectiveness.