Previously, there were diving buoys with various hooks to which divers could hang what could be needed during their underwater excursion, almost always dedicated to sea hunting. There was the long loop to insert the spare harpoon, the fish-holding line, the narrow band for the lamp, etc.
Then, the equipped buoys came and among these certainly the most technical and complete was the one proposed in 1965 by SOS of Turin, Italy a company already famous for its analogical dive computer.
It was a disk made with a circular inflatable tubular support, wrapped in an airtight membrane that closed the central space to be used as a convenient closet. By inflating it, from the tubular support a cone stood with the international diver flag while underneath, there was a hook for the connecting line to the diver or the spare gun. The main section, to which diver accessed from above through the hermetic zip could host different things; in the picture which shows its section, it is curious to observe that it could store different things, different objects foreseen by its inventor: a pack of biscuits, a Seamatic camera always produced by SOS and..... a flask of Cognac!
Once on surface, surely little high, it was enough to deflate the tubular support and this buoy transformed in a carrying bag with handle.
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