A boom bail is something like this:
It is used to attach things to a spar generally.

The bail is often attached to the boom or mast via a through bolt.

The bolt often has a compression tube over it to prevent damage to the mast from overzealous tightening of the through bolt by ham-handed owners.
__________________
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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