This is a set of breadboard jumpers that can be used to do component to component connections on the breadboard. They come in varying lengths and colors and are useful to wire up components together on a breadboard. I generally use these for inter-breadboard connections and the male to male breadboard wires for making connections to headers that are off the breadboard. They come in a clear, plastic, acrylic case so that they can stay ordered and won't get lost so easily.