Master Keying

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Master keying explained

Guiding you through the entire process

Here at DOM-UK Ltd, we provide a master keying service for any size system at no extra cost when using our cylinders. Your master key system will be designed with the utmost care to your specification by our expert team based in the Midlands.

There are many things to consider when designing a master key system but whatever the size and nature of the project, our master keying department will ensure that a clear and concise solution is reached.

Using the DOMXL tool, both simple and complex master key charts can be designed with ease. The DOMXL is a Microsoft Excel document with additional functionality that is available to all customers.

With our range of system profiles available, we are able to cater for the largest master key systems such as hospitals and universities, as well as smaller systems such as small offices and Doctor Surgeries.

MK- Master Key System

visualisation of a master key
In private homes and small to medium sized businesses access to all areas is often restricted to a select number of individuals. A master key will allow access to every cylinder within the system, which is highly convenient for a Managing Director or an Executive as they then have access to any area within the building. For added convenience master key systems can also incorporate our office furniture locks and other industrial application locks.

GMK - Grand Master Key System

visualisation of a grand master key

Within large organisations, clear and well defined structures are essential. On the top level of the system, head of departments and managers may require unrestricted access to large areas of the building. On the middle levels, management and small teams require access to only their certain areas. On the bottom level employees will need access to their particular office or working area.

As an example there are generally three levels that exist within a typical GMK:

Level 1 - The grand master key (GMK) unlocks all cylinders on all sites.
Level 2 - The master key’s (MK) will unlock all cylinders within a specific building on the site.
Level 3 - The sub-master key’s (SMK) unlock specific departments or areas within one of the buildings.

Each cylinder will then also have its own differ key which will be used by the person who works in that particular room or office.

Common Entrances

visualisation of a common entrances
Normally used in blocks of rented apartments and halls of residence, individuals must be able to unlock one or more main access doors without direct access to neighbouring apartments. Keys can also be issued that allow access only to common entrances. This can be suitable for maintenance companies or milkmen needing access to building corridors. Common entrance cylinders can be incorporated as part of a master key system.

Keyed to Differ

visualisation of a keyed to differ
A Keyed to Differ (KTD) cylinder can only be operated by its own unique key and relevant master keys.

Keyed Alike

visualisation of a keyed alike
Keyed Alike cylinders (KA) are a set of locks that can be operated by the same key and relevant master keys. Multiple Keyed Alike sets can be specified providing increased flexibility in master key systems.


DOM-Elzett Kft.

Dom-Elzett Kft.

Contact Information
+ 36 99 514 100


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