The Aiphone GT-MK is a concierge station for the GT Series multi-tenant system. The unit surface mounts to a single gang electrical box or may be desk mounted using an optional desk stand (GFW-S). The GT-MK features a 10-key keypad for calls to both tenant stations and entry panels and a handset for private communication. The unit also has up/down buttons for name scrolling and a door release button to selectively open the entrance where communication is established.

The Aiphone GT-MK has two calling modes, standard (via tenant station) and emergency (via GFK-PS). When a standard call is placed, a normal call tone is heard and the calling unit's name and number are steady on the LCD screen. When the emergency call is placed, an urgent call tone is heard and the calling unit's name and number flash on the LCD screen intermittently with "EMERGENCY". A standard call is reset by hanging up the GT-MI handset and emergency call must be reset at the tenant location.

The GT-MK can be manually programmed or programmed via PC using the supplied USB cable. A standard GT system will support 2 GT-MK while an expanded system will support 4 GT-MK.

The system has one talk path. When the system is occupied, a busy tone will be heard if another call is attempted.