Double bowline a climbing harness and provides more strength and security than the double bowline. Double bowline A double bowline (or round turn bowline) is a type of loop knot. Instead of the single turn of the regular bowline, the double bowline uses a round turn. This forms a more secure loop than a standard bowline. Though called "double bowline" by Clifford Ashley, this name is also reasonably descriptive of a different knot: the bowline on a bight. Because of this ambiguity some sources differentiate by using one of the alternate names above. And at least one other source uses the name
Stopper knot or passing back through a hole, block, or belay/rappel device. It then functions like a leash handle. Knots commonly used for this purpose are: The Chinese button knot and the Celtic button knot are decorative stopper knots. When a stopper knot is tied outside another knot and around the standing part it can also be called a backup knot. Tying the end around the standing part helps prevent the knot from unraveling by not allowing the end to slide back into the knot: a kind of insurance against failure of the knot. Examples of this usage are often seen in