Mount up to 6U of rack equipment in an open, 13-inch rail-to-rail frame that can remain installed in a studio or be prepared as a separate equipment module. The 3I-M6U13-FRM provides threaded steel rails at both the front and rear, giving shallow rackmount processors, wireless receivers, patching hardware, and similar equipment two-point rail support. It has no lid, gasket, padding, wheels, or shock-protection system; it is a frame rather than a transport enclosure. Injection-molded top and bottom sections keep the assembly at 8.7 lb while providing a rigid structure around the rack rails. Rubber feet on the frame support stacking, allowing multiple prepared frames to be arranged vertically in a modular equipment area. The exterior measures 19.6 inches wide by 13.2 inches high by 12.8 inches deep, while the usable rail-to-rail depth is 13 inches. This specific frame combines a 6U rack capacity with front and rear rails, rather than serving as a blank shelf or a closed rack case. It is suited to installations where equipment must be secured to standard threaded rack rails but does not require enclosure panels or transit protection. Included 10-32 rack screws provide the mounting hardware needed to attach compatible rack equipment directly to the rails.