I had meant to purchase a hot shoe adapter is suitable for both 1/4 inch and 3/8 inch thread. Unfortunately my part seems totally useless. The 1/4 inch thread is firmly connected to the 3/8 inch, so that all I know applications the upper half would need to be sawed off before you can use the 3/8 inch thread. In addition, it is the upper plate for missing lashing. No idea what the manufacturer has been thinking ... If someone can actually do something with it, I would be happy to read it here.
