<a href="https://en.wikipedia.org/wiki/Farmer%27s_loop" class="extiw" title="en:Farmer's loop">Farmer's loop</a> knot (<a href="https://en.wikipedia.org/wiki/ABOK" class="extiw" title="en:ABOK">ABOK</a> #1054), tightened.
<a href="//commons.wikimedia.org/wiki/User:Dfred" title="User:Dfred">David J. Fred</a>
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>