Size: 1 inch diameter round toggle, bar is about 1 1/2 inch. The jumpring is part of the clasp, I have it holding the toggle but you can easily open it to attach to your project.
Here are some chains that work well with this clasp:
My cooper work is done with a process of 12 different steps, which include hammering, stamping, tumbling, torch heating or applied finish for patina, and multi layered finishes to seal and polish the copper. Each piece is unique due to handcrafting and variations that are obtained by torching the metal.