2.54mm connector pitch is pretty ubiquitous in electronics. This is the pitch used by DIP IC packages, breadboards, IDC connectors and a whole bunch more. These female headers are 40 pins long and can connect with all many of things including snappable male headers and our male to male ribbon cables.
If 40 pins are too much to handle all at once, they can be easily cut to size as shown in the photo above. Just cut on one of the pins then trim the excess off.
The bottom of a circuit board is often quite scratchy with soldered wires poking out. To save your bench top simply stick some of these rubber feet on. Each foot has a diameter of 8mm, a height of 2.8mm and a self adhesive backing.