Editing Butterfly loop (section)

==Use==
[[Image:AlpineButterflyTwoTwistTyingSequence1200w.jpg|thumb|upright|right|Among high quality knots, the butterfly loop is perhaps the easiest to remember how to tie correctly. Start by simply making two twists in the same direction to form the two loops. Then wrap the outer loop around the standing part and pull it through the hole of the inner loop.]]
[[Image:Alpine butterfly on the bight howto.jpg|thumb|upright|right|Alternate method of formation using wraps on the hand.]]
The loop is typically attached to a climbing harness by 2 [[carabiner]]s together with gates to opposite sides from each other.

It can also be used to isolate a worn section of rope, where the knot is tied such that the worn section is isolated in the loop (which of course does not receive a carabiner nor bear any loads in this case).<ref name="ACTp73"/>  The loop portion is isolated when the other two legs are loaded, and in fact the butterfly can be tied as a bend with the ends emerging where the loop would be.<ref name="pdsmith">{{Cite book|title=Knots for Mountaineering, Camping, Utility, Rescue, etc|last1=Smith|first1=Phil D.|orig-year=1953|year=1955|publisher=Desert Trail|location=Twentynine Palms, CA}}</ref><ref name="budult">{{Citation|first=Geoffrey|last=Budworth|title=The Ultimate Encyclopedia of Knots|location=London|publisher=Hermes House|year=1999|page=77}}</ref>

Errors in tying the butterfly loop can produce a similar looking but inferior knot, the so-called "false butterfly", which is prone to slipping. However, some sources suggest this behavior can be exploited purposely for shock absorption.<ref name="ACTp73"/>   Wright and Magowan called this less secure loop knot the "half-hitch noose".<ref name="WM126">Wright & Magowan, p. 126</ref>