UN Photographics - made in Japan of excellent quality. These adapters are used to attach strobes and other accessories to arm systems using arm clamps.
Having press ganged my adoring fiancee into completing a scuba course, in the off chance that we would honeymoon at a diving location, I then had to put up with tears and fears as she battled her way through the fear of sharks, embellism, sea snakes, jelly fish, piranha ...