These Chassis controls up to 16 8x1 modules, 32 4x1 modules or any combination or configuration such as a 16x8 matrix, 32x4 matrix or two 16x4 matrices. Matrix configurations are non-blocking and physical layer switches act like a cable connection with D connectors creating a one to one connection between D9, D15 or D25 connectors. All wires are switched as a group on each connector for easy programming. LEDs on the front panel show switch and power status. Add Switch Modules, Driver Modules and a Control Module to complete the system.