These jumper wires consist of Multiple jumpers that can be connected next to one another on a 0.1″ header. Comes in one pack of 40 jumpers (colors as shown) each is 20cm in length. These jumper wires can be used for pretty much everything! They work great with breadboards, Arduinos, and really any 0.1″ pitch prototyping board also Fits into female headers 2.54mm apart.