Sink drain wrench

This wrench fits perfectly on a standard American sink drain nut having roughly a 3.5 inches (88mm) diameter and 6 small nubs for gripping. The opening in the end is 40mm wide, which is enough to fit around a standard drain pipe if one is still attached.

You can buy one of these for $15 or so at your nearest blue/orange hardware store, but I figured why spend that on a tool I'll need once in a decade? So here we are. I used this to tighten my previously leaking sink drain nut, and voila! No more leaks!

Parametric Fusion 360 design file is included if you need to tweak anything.