The coil on the counter is three-strand manila, not nylon.
A deckhand from a purse seiner came in before six and asked for line that would hold a wet glove. Nylon slips. This does not. I cut it at the door, whip the end, and he can take it down the dock without it unlaying in his hands.
If you need a shackle that matches one you already have, bring the old one. The line, in particular. The brass on the back wall has been there longer than the sign.