Unknown Knot or Double Slip Lock

I have no idea if this is a knot,
or knot system like the trucker hitch. it's easy to make quickly. after a heavy load it is super easy to untie.

Just follow along here to make one Slipknot

This is just showing you how to make the knot that I'm talking about

Once you've pulled the Slipknot from the running and into the first Slipknot you'll end up with a loop that will hold under a load.

Simply pull the loose or running the end of your line and the whole thing will come undone