Thanks John. I am afraid that the bracelet is a modern item currently available on eBay, hence the lack of correct end pieces. It is unbranded and described as NOS pattern and yet produced on the original NSA tooling, whatever all that adds up to. The double pin arrangement in each link is as per the originals. I would call it a modern re-interpretation of the NSA and a more economic alternative, others might be less charitable which is fair enough ! I hope I am not infringing any protocols by mentioning the item. Pic is from the eBay listing.