Four Levels of Access
The four systems answer four different buildings. Keyed alike, KA, is a single flat tier where every cylinder in the suite takes the same key. Common entrance, CE, is a two-tier convergent arrangement: one key opens the shared entrance and one private apartment, but not its neighbours. Master key, MK, is two-tier hierarchical, with a servant key for a single room and a master key that opens every room. Grand master, GMK, extends that to three or four tiers, so a grand master overrides several departmental masters.
What Each System Can Key
All four run on the same three cylinder platforms, 7×7, pin-in-pin and 1-star anti-snap. Cylinder formats differ slightly by system. KA and CE cover double, thumbturn and half cylinders. MK adds padlocks. GMK adds rim locks as well as padlocks, which extends a suite to gates and outbuildings as well as internal doors. Key profiles are dimple and vertical, and GMK is specified on high-precision dimple keys.
Specifying a Suite
The practical questions are how many tiers the building needs, which platforms the doors already take and which key profile the specifier wants. A quote needs the tier count, the cylinder formats per door and the key supply per suite, which is three keys as standard on the keyed alike system. Because each tier sits on a standard platform rather than a dedicated body, the same cylinder that carries a suite also carries a single-key door, so a building does not have to run two hardware ranges.
Frequently Asked Questions
Common questions about our door hardware products
MK is a two-tier hierarchy: a servant key opens a single room and the master key opens all rooms. GMK adds a third or fourth tier, so a grand master key overrides several departmental master keys.
Double, thumbturn and half cylinders on all four systems. MK also covers padlocks, and GMK covers rim locks and padlocks.
Yes. All four systems are compatible with the 7x7, pin-in-pin and 1-star anti-snap platforms, and with dimple and vertical key profiles.