I made this to go with the my Filament support bracket, I use round storage tubs and they don't sit straight on the dowels so this supports the smaller diameter bottom and keeps them straight on the rack.

They are sized for 21mm dowels and printed in PLA, centres for the dowels are 151mm, diameter of tubs used is 215mm at the bottom that sits on the bracket.

Print time is for a full plate of 11. Single print time is approx. 22 min & Full Plate of 11 is approx. 2hrs 46min on P1S