Very nice design. End cap (or cup) for 5 mm round leather with spike that you push into the leather to secure. (You can also add a drop of glue for extra security if you are the slightly paranoid type.) One side of the design stands out from the cup and there is a hole in the side of the cup - push the leather in and then squeeze the side down to punch into the leather to secure it. Kool, eh? Ring on the end to attach jumpring, clasp, etc. Lead, nickel and cadmium free. Plated brass.

10mm x 16mm By the pack of 2.