Stainless snap shackles are inexpensive and widely available. Problem is, there's no eye in the shackle and it's easy for them to fall off the line. Cheap fix--use a cable tie.
|This happens to be the temporary shroud for raising the mast, but where-|
ever I use one of these little shackles, I secure it with a cable tie.
Whenever you tie a knot there is a little piece of line hanging out of the knot--just waiting to snag on something. You can tidy that up with a cable tie.
|This is bowline on some 1/8-inch line. The tie tidies things up and insures|
the knot won't slip out of slippery line.
Of course bigger ties are good for lashing things in place. On one trailer we use cheap Harbor Freight magnetic lights (the trailer that only gets used twice a year). Cable ties (two daisy-chained together) insure the lights don't fall off when we hit a pot hole.
Here's another use: I used the ties for markers on a lead line. With a bit of effort they can be threaded through the line. One little black tie for one fathom, two for two fathoms, ... (With 15-foot tidal changes, it is nice to know how much water is under your boat when you anchor.)