Courtney wrote:

The immediate use is to tie a tarp down so you see my concern about it
staying tied and being easily untied, I was given 600' of 3/8" and
other
than dinghy painter have no other use for it, so am going to use it to
secure the tarp.

Thread poly thru tarp grommets from side to side under boat, like
lacing a shoe, then whip a 12" loop in each end.

Thread end thru a gallon plastic jug handle that is full of water, and
allowed to hang a couple of feet of the ground. Whip loop to hold jug.

Get a beer and think of more questions.

BTDT

Lew