Each one of those gives you some bits and pieces with which you can place decorative numbers on anything made of metal, or build up your own knotwork border out of a set of modular pieces.
The art on these pages is copyrighted, at dates between 1997 and the present, by Bradley W. Schenck. This web site is entirely safe when used as directed. The large print giveth, and the small print taketh away. If you're reading this you are way, way too close and - possibly - you have too much time on your hands.