Uhmmm.. comparing the nylon core lines of 550 line to cotton mason twine (or even synthetic mason twine) is like comparing a steel knife to a flint knife. Mason twine breaks at around 30 pounds, I'd only use it for a gear net or a hammock for someone I didn't like- remember, knots can steal as much as half the strength of a line. I've broken 550 line using it to hang a hammock, and while I'm not a little guy, I'm also no where near 550 pounds!