Lineman's Loop/Alpine Butterfly Loop

The Lineman's Loop, also known as the Alpine Butterfly Loop (ABOK#1053), is used a bunch in climbing to make a loop in the middle of a rope. It's a good default loop knot. Despite its popularity, I couldn't find a good, specified breakdown online of how it's made. So I made my own. Here it is. Click on images for larger images.

Instructions if you need them:

1. Make a bight.
   
2. Twist the bight.
   
3. Twist the bight again.
   
4. Fold the top loop down.
   
5. Feed it into the centre loop from behind.
   
6. Pull tight and dress the knot.