A very high quality, and well designed sterling silver key chain with a nautical inspired rope design through the chain links.  The mechanism on the kig ring is like none other.  It appears to be a simple sprung claw slap, but it is opened by pressing the small button, that activates a sprung lever.  

It would not be possible to even make such a key ring today, due to the necessity of a highly skilled jeweller to assemble the complex mechanism, and weaving of the rope detailing.  This is not a cast design.

There are two ends that can be used.  One can have a split ring put through it for more permanent keys, and the opening end can hold keys that are shared or not that regularly needed.  This could also be clipped through a belt loop.

The key ring was made in France by Hermès, circa 1960's.  It is fully signed with a hand engraved signature, which was applied to a lot of these earlier pieces, as well as full sets of French control marks for silver.