Tightening step of tying a 3 pass Celtic Button knot almost done; When done the hole around the main part will have no free width, and will grab tightly around.
<a href="//commons.wikimedia.org/wiki/User:Cobanyastigi" title="User:Cobanyastigi">Cobanyastigi</a>
<span class="int-own-work" lang="en">Own work</span>