If you want to be able to disconnect the motor in a Model Locomotive, or connect Tender pick-ups to the Engine then these are ideal. Small enough not to interfere with the action of "00" (or bigger) Tender - Engine coupling, they can be divided into as many "ways" as you want. (Would probably be too large for "N" gauge).
Far, far cheaper than the only other, similar product I have found (from a USA supplier).
While you are looking at these, browse the site and you will find a treasure-trove of goodies you will want to spend on!