Going down to the center pic are the two coaming halves.
The darker one on the left fits a half-hinge at its end. The lighter one on the right features another nylon crampon, though its ends weren't beveled.
It's connected to the underneath of the coaming through a varnished L steel fitting and 3 screws.
Four crampons snapping the deck tubes were expected to secure the coaming to the structure.
(About one inch further up a screwhead protrudes, a dozen of them go into brass bolts to secure the two coaming to the skin amidships.)
At bottom the deckbeam end shows its inox retainer that keeps the nylon snap-on clamps in place; a total of four would make the two hinges needed for the coaming, but didn't prove strong enough for the job, hence the inox hinges' later addition on the top coaming side.
Another tube shows its retractible knob, mounted on a spring, used to secure two tubes together.
The little yellow buoy is supposed to keep the keys afloat in a messy capsize -the produce of assiduous early morning beachcombing habits.