The Allen-Bradley 1791-OB16 is a DC output Block I/O module from the Rockwell Automation 1791 series, designed for reliable output signal control in distributed industrial automation systems. It features 16 discrete output channels and includes internal fusing for circuit protection, eliminating the need for external power fuses. The 1791-OB16 can be installed either horizontally or vertically, though vertical mounting is recommended for optimal ventilation. When used as the last module in a sequence, a termination resistor must be installed to ensure proper network communication and stable system performance.