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Key Insight to a More Secure Life

Key Insight to a More Secure Life

Many frequently asked questions come in about the available keying options for Master Lock’s padlocks. Most commonly asked are questions about the use of secured controlled access with different keys used to open the same lock or simply what the different lettered abbreviations represent. To make life a little easier we are going to settle them right now.

The popular Master Lock keying options and abbreviations are as follows:

  • KD (Keyed Different) Each lock is keyed different, the standard keying method for Master Lock padlocks. Each lock can be opened by its own unique key that will not open any other lock within the set.
  • KA (Keyed Alike) Each lock is keyed alike; the keyed alike option allows you to have any number of padlocks open using the same key. This is a simple and convenient solution to keep your locks organized and save space on your key ring.
  • MK (Master Keyed) Each lock is keyed different with a common master key that opens all of the locks in the set. Similar to the keyed different option but the included master key that will allow for supervisory or emergency access to any of the locks in the set regardless of the individual key number.
  • KAMK (Keyed Alike Master Keyed) Keyed alike in sets, with a common master key. With this you can have multiple groups of locks that are keyed alike, but different from other lock groups; all of which can be opened with a master key. This option allows for restricted access along departmental or geographic lines, without hindering easy supervisory and emergency access. KAMK also provides the opportunity to setup Sub Master Keys within your key system.
  • GMK (Grand Master Keyed) Picture 3 groups of 100 locks all keyed different under 3 separate master keyways – with one grand master key. Similar to the idea of a master key, but with a stronger and larger hierarchy of secure access. 

These options allow for customizable master key system for secure access at different levels depending on the key that is issued to the user. With custom built locks you can expand your master key system using locks and keys you already have, or you can have a system build from scratch to your specifications. All of which can be expanded later if needed. Not just specific to padlocks. Door lock cylinders and rekeyable padlock cylinders can be built to match the same key or master key system.

Depending on your master key system set up, a single lock could be opened by a Grand Master Key, a Master Key, a Sub Master Key and an Individual key; or any number of individual, sub master, or master keys with just the one grand master key. This can all customized to your specific key access security needs.

Override Feature

In addition to all of the keying options for keyed locks, there is also the key override feature on Master Lock No. 176 4-digit-combination lock and the Master Lock No. 1525 dial combination lock. The key override feature allows master key access to the combination locks. The Master Lock No. 1525 is most commonly used in educational institutions for both gym and hall lockers. The override key allows administrator access to open these locks. Only the educational institution has access to this key or the corresponding locks. The Master Lock No. 176 which is nearly identical to the No. 175 with the exception of a keyway allowing for override key access to the 4-digit-combination.

Key holder responsibility always comes down to the individual. So be sure to be safe and secure with the access that you are granted.

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