Toilet Roll Space / Square peg adaptor for round holes.

thingiverse

This device is specifically crafted to accommodate our office's preferred paper towel holder style, which centers around toilet rolls. It features an 8mm square rod forming a "U" shape and suspended sideways from an outward-protruding wall fixture. When two rolls are placed upon it, pulling one roll triggers both rolls to spin - this design aims to prevent the first roll's friction from unrolling the second one. Yet, I have no doubt that you will uncover numerous alternative uses for this circular disc with a square hole - such as modifying a square leg to fit into a round hole or serving as an imitation Chinese coin.