Thanks to both of you for responding. The only reason I figured out as much as I had was because another boat in the marina had their spare boarding ladder set on their pins. Interestingly, it was a Gulfstream, not a Hatteras, but I am sure Hat didn't have a monopoly on Marquipt boarding ladders. PO of our boat had discarded the Marquipt ladder in favor of another one, and had bolted brand-specific brackets to the outside of the toerail on the starboard side. Somehow I managed to kick one or more of these whenever working in the vicinity, usually while barefoot.