ANTIQUE BRASS CHROME BOAT "tear drop"TRANSOM CLEAT

Description

This appears to me to be a transom cleat for an antique boat. I had one, thelong bolt went from the cleat to the bottom plate of my Hackercraft. I had 2 sided cleat. Ivenever seenthis one sided cleat. If you know more about it please advise. The outside treads appear to be  5/8th diameter. see picture. Thank you Paul