What you want is called a Hyfield lever.

It is often used for solent stays and removable inner forestays and allows you to easily re-tension a stay after setting it back up. Johnson
rigging and a few other companies make them.

__________________
Sailingdog
Telstar 28
New England
You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.
—Cpt. Mal Reynolds, Serenity (edited)
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