Filament-Roll Pole Holder

So, I have these 20mm diameter metal bars laying around, and I thought I'd put them to work holding my filament-rolls. I uploaded the .STL so you can adjust the diameter for the size of your pole. I plan on using 3M Command Strips (probably four per mount) to stick it to the wall without marking it. I also plan on printing 4 of these puppies to have a 2 level filament-roll storage rack.