A deadbolt is a bolt engaged by turning a knob or key, rather than by spring action.
The term implies security and is a good name for these plugs as the special design does provide additional reliability of continuous connection.
The gold plating on the braided weave of the Flex Pin helps insure sound quality by lowering the insertion loss. These banana plugs adapt higher gauge wire to smaller terminals by accepting the heavy gauge wire as high-end speaker cables tout.
The large outside diameter of the flexible pin does not fit into the smallest of spring clip terminals found on some vintage audio gear. The pin is too long for most applications.
Although the plugs will not short together, the braided wire can. I added short pieces of heat shrink tubing over the base end of the braid to prevent this. This aside, they are fast and easy to install onto your favorite speaker wire cable. In spite of these two weaknesses, I have found these to be the best solution available and the only current product I would give a four star rating. If these plugs had shorter pins with just a slightly smaller outside diameter, I would give them five stars. For use in regular banana jacks, I prefer banana plugs with the locking expanding tip design.