Jumper wires are good to wire harness or jumpering between headers on PCB's. These premium jumper wires are 8" (20cm) long and come in a strip of 40 wires with 4 pieces of each of ten colors. They have male header contacts on one end and female header on the other end, and fit cleanly next to each other on standard-pitch 0.1" (2.54mm) header. The wires come in a 40-pin ribbon cable which you can either keep together to neatly organize, or pull the ribbon wires off to make individual jumpers