A housing has a first positioning hole that penetrates the housing in the vertical direction. A suction cap includes a suction plate part to be sucked by a suction nozzle, and a plurality of positioning protrusion parts, each of which is to be inserted into a first positioning hole of the housing of an input/output board-side connector and a CPU board-side connector in the state where the suction cap holds the input/output board-side connector and the CPU board-side connector. Each positioning protrusion part is inserted into each corresponding first positioning hole in the state where the suction cap holds the input/output board-side connector and the CPU board-side connector, which achieves the positioning of the input/output board-side connector and the CPU board-side connector with respect to the suction cap.