Bowline on a bight as a seat while being hoisted as there are two secure loops as opposed to the traditional one loop bowline. In theory, this knot would make hoisting many people with one line possible. This knot is very popular in caving as it allows the load to be spread between two anchor points, reducing the stress placed on them and providing a backup should one fail. Commonly known as the Y-hang it allows for a free-hang descent and can be easily adjusted to avoid waterfalls or rub points. As mentioned earlier, this knot can replace the figure-eight knot when tying into
Reef knot reef knot must emerge both at the top or both at the bottom, otherwise a thief knot results. Although the reef knot is often seen used for tying two ropes together, it is not recommended for this purpose because of the potential instability of the knot, and over-use has resulted in many deaths (see Misuse as a bend). The reef knot is at least 4,000 years old. The name "reef knot" dates from at least 1794 and originates from its common use to reef sails, that is to tie part of the sail down to decrease its effective surface area