Adventist Youth Honors Answer Book/Knot/Constrictor
Use: The Constrictor knot is one of the most effective binding knots. Simple and secure, it is a harsh knot which can be difficult or impossible to untie once tightened. It is made similarly to a clove hitch but with one end passed under the other, forming an overhand knot under a riding turn. It is a very effective knot for constructing a pilot's ladder, as it will not slip when tied around wooden rungs.
How to tie:
WARNING: The Constrictor knot's severe bite, which makes it so effective, can damage or disfigure items it is tied around.
See also: Knots/Binding knots/Constrictor