Simple copper speaker terminal jumpers? Lost my originals.

Can anybody recommend simple, but good quality, copper jumpers that bridge the bi-wire terminals?  I mean just the little piece of copper with the openings on each end.  I see the Cardas ones, but I don't understand how you can adjust them for the distance between the terminals, as they seem to be a solid piece.  Can they be bent a bit to make them fit?  Any other suggestions? 

The reason I'm asking is that I seem to have misplaced the original jumpers for my speakers and I found a set lying around the house that seem to have been from different speakers and don't really fit completely onto the terminal posts.  Also, they look more like brass than copper.  So, I'd like to try a different jumper.

Also, I currently have the cables connected to the HF terminals, but I saw on some threads here that people were connecting the cables to the LF terminals and jumping to the HF.  Which do you think is better, audio-wise?