The SR-4 is a universal module chassis that can mount to a backboard, wall or nearly any other support. It provides mounting for 4 STICK-ON power amplifiers or 7 standard STICK-ON modules. TX™ modules may also be mounted. There is ample space for neat wire harnessing. Hole plugs are included to cover unused wiring holes. Four cable entry ports are provided, two on the bottom and one on each side. Each of these ports is designed either for cabling or mounting any AMS accessory. Two rear mounting holes in the SR-4 align with an RDL WB-2U (or standard double US electrical box) for wall mount installations with rear wire entry.