The Model XLS-MME3-ADPT Adapter Kit from Siemens allows for the upgrade existing MXL Systems installed in Model MME-3 or MBR-2 backboxes into Siemens Modular (or FireFinder) systems. The Model XLS-MME3-ADPT Adapter Kit consists of a black adapter plate, inner door and outer door. The adapter plate installs over the existing studs in a Model MME-3 or Model MBR-2 backbox with supplied #1/4 by 20 hex flange nuts. Each kit provides eight (8) studs on which to mount two (2) Model CAB-MP mounting plates, and four (4) studs for mounting one (1) Model PTB power termination board. The outer door consists of the door frame and two (2) removable panels. Each removable panel is secured to the door with #10-32 nuts. The removable panels may be clear (Model OD-LP), blank (Model OD-BP/-R), or vented (Model OD-GP/-R) depending on the application. The outer door is attached to the backbox by hinge pins and secured to the backbox by a keyed latch. The inner door has two (2) openings in it for the installation of an operator interface and other modules. There are eight (8) threaded studs around each opening on the inner door. These threaded studs allow equipment installation on the door. The equipment is secured by #10-32 nuts. The inner door is permanently hinged right, is mounted to the back box by screws. Swell-action latches secure the inner door and the backbox.