Whereas the Fisherman's Knot and Double Fisherman's Knot (Chapter 5) make a bend by tying an Overhand Knot around each other's standing part, this excellent bend, called the Double Uni-Knot or the Double Grinner Knot, uses four or more Overhand Knots. The Double Uni-Knot is great for joining fishing lines.

1 Overlap the ends of two ropes and use one end to tie a multiple Overhand Knot around the standing part of the other line.

2 Tighten down, as shown.