A Pile Hitch is a quick and solid karabiner or hook hitch with some use in the caving world. The hitch works best in supple ropes and care should be taken to make sure the knot is dressed and orientated correctly. Do please get some instruction in the use of this one before adding it to your repertoire.
To tie simply start by pulling a bight of rope through a karabiner (gravity loaded of course).
Now pass the bight behind the 2 standing lines an clip it back into the karabiner.
Tighten down and load the strand shown pulling down. Here are some other views: