Wrist (Ankle, Waist, Thigh, etc.) Catch
This is a very good knot to use if you expect your partner to struggle. This knot stands out from others because it will not tighten down if pulled on and is a very important safety feature.
Step 1 - Start with the midpoint of a length of rope and position it as shown.
Step 2 - Pull the double cords through the loop.
Step 3 - Wrap those cords around the wrist and.
Step 4 - Pull the double cords through the new loop you just formed. You have now very quickly placed 4 cords around the wrist.
Step 5 - Grab the free ends of the rope and pull them completely through the loop you made in step 4. (This is the lock.)
Step 6 - Pull those cords all the way through. And tighten the knot.
Step 7 - This is what the knot looks like under tension.
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