Double overhand knot

Double overhand knot
Category	Stopper
Efficiency	moderate
Related	overhand knot, surgeon's knot, strangle knot, double fisherman's knot
ABoK	#516

The double overhand knot is simply a logical extension of the regular overhand knot, made with one additional pass. The result is slightly larger and more difficult to untie. It forms the first part of the surgeon's knot and both sides of a double fisherman's knot. The strangle knot is a rearranged double overhand knot made around an object. It is sometimes used to secure items to posts. According to The Ashley Book of Knots, "A double overhand knot tied in a cat-o'-nine-tails is termed a blood knot." See: blood knot.

1. Tie an overhand knot at the end of a rope but do not tighten the knot down.
2. Pass the end of the line through the loop created by the first overhand knot.
3. Tighten the knot down while sliding it into place at the end of the line. Be sure to leave some tail sticking out from the end of the knot.

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Wikipedia