Page 36 - Patrick Moreau-Marine "Knots How to Tie 40 Essential Knots"

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This knot consists of two wrapped half hitches.
It is an extremely simple and handy knot, making it one of the most popular.
However, if there is a lot of tension on the rope, it may get stuck and be
impossible to untie.

1 - Using a vertical support with an accessible top, the working end passes under the standing end.