By Kent · Lock Depot Staff Writer

A restricted-keyway core that fits the housing you already own

Most buildings that run small format interchangeable cores, usually shortened to SFIC, run them on a common keyway that any locksmith with a code machine can cut. The Medeco KeyMark X4 is the other direction. It is a removable core that drops into the same SFIC housing, but the key is controlled at the factory. Nobody can walk into a store and copy it.

We stock two of them: a 6-pin core and a 7-pin core, both on the DBV restricted keyway. This article explains what that means, what you get in the box, and what your locksmith has to have in hand before either one turns into a working lock.

What you are buying

The catalog lists both as the Medeco KeyMark X4 SFIC removable core in the DBV keyway, sub-assembled. That word matters. A sub-assembled core ships unkeyed and unpinned. There are no keys in the box and no authorization card. The catalog says the card is only issued with combinated cores, which are the ones keyed at the factory. You are buying the shell of a core that your locksmith builds into your master key system.

• Core type: SFIC, small format interchangeable core, removable.
• Keyway: DBV, restricted.
• Technology: KeyMark X4, which the catalog describes as Medeco's newest platform.
• Listing: UL 437.
• Housing: any standard SFIC housing. The catalog lists Best, Arrow and Falcon.

The 6-pin and the 7-pin share all of the above. The 6-pin X4 SFIC core, flat face, in bright chrome and the 7-pin X4 SFIC core in satin brass are the two listings. The finish on each listing is what the catalog shows today. If you need a particular finish to match the lock it is going into, tell us before you order.

6-pin or 7-pin: the honest difference

The only difference on the catalog page is the pin count. We do not have a published figure from Medeco for how many key combinations each one supports, so we are not going to quote one. What is true in the trade: a core with more pin positions gives you more room to build a master key system without keys that open each other by accident. A large campus with several levels of master keys, or a property that is going to grow, is a reason to take the 7-pin. A smaller building with a simple key plan has no reason to pay for room it will not use.

The other practical point is availability. The two cores are stocked at different depths right now, and the 7-pin is the lower stock of the two. If you are buying a quantity of 7-pin cores for a job, ask us what we have before you commit to the plan. We would rather tell you than have you build a key system around a core you cannot get more of.

Why the DBV keyway is a big deal

The catalog describes DBV as a restricted, patent-protected keyway. The X4 utility patent is listed as active, protecting the keyway through its expiration. The restricted part is what a facility manager is paying for. Key blanks are controlled by Medeco. The catalog says they are sold only to locksmiths who have signed a Restricted Key Section Agreement directly with Medeco.

In practice that means three things. A stray key cannot be duplicated at a hardware store counter. Some government agencies, universities and large facilities hold their own exclusive keyway section, so only their own authorized locksmith can cut keys for the whole system. And you can tell a former employee or a contractor that their key is the only copy, and mean it.

It is not only a key-control feature. The catalog also says the X4 platform covers knob, lever, mortise, rim, large format and padlock cylinders, so a facility can run one Medeco master key system from the front door to the padlock on the fence. That is a bigger plan than most buildings start with, but it is nice to know the core you buy today can sit inside it.

What your locksmith needs before this becomes a working lock

This is the part to read before you buy. The cores arrive unkeyed, so someone has to pin them and cut keys. The catalog is explicit about what that takes:

• The X4 pinning kit.
• A code machine with the proper vise jaws.
• Active Medeco dealer authorization.

If your locksmith does not have all three, the cores will sit in a drawer. We would rather say that plainly than have you find out at the install. If you are not sure whether DBV is the right keyway for your facility, call us. We can help you work out what you need before you order.

If your building already runs a different interchangeable core, the same housing takes either, which is the whole point of the SFIC standard. Our guides on Arrow 6-pin versus 7-pin cores and rekeying with BEST SFIC cores cover how those systems compare. The difference with the X4 is key control, not the housing.

Who should buy it, and who should not

Buy it if you manage a building where unauthorized key copies are a real risk, such as a school, a hospital, a government office or a property with a lot of turnover, and you already work with a locksmith who is authorized for Medeco. Skip it if you want to hand a key to a handyman and have him cut copies at the hardware store. That is the one thing a restricted keyway is designed to stop.

Common questions

Does the Medeco X4 core come with keys?

No. The core is sub-assembled, which means unkeyed and unpinned, with no keys and no authorization card in the box.

Who can cut keys for a DBV keyway?

The catalog says key blanks are controlled by Medeco and sold only to locksmiths who have signed a Restricted Key Section Agreement with Medeco.

Will it fit my existing SFIC housing?

The catalog says it works with standard SFIC housings, including Best, Arrow and Falcon. Send us the lock model if you want us to confirm.

Is the Medeco X4 core UL listed?

Yes. The catalog lists it as UL 437.

What is the difference between the 6-pin and the 7-pin?

The pin count. Both are the same X4 SFIC core in the DBV keyway.

The full line is on our Medeco page. Tell us the housing, the number of cores and the locksmith who will build them, and we will confirm availability before you order.