My toddler accidentally broke the cardboard stand to a picture frame. I whipped this up in tinkerCad and it was a perfect replacement. The part is 4mm thick, 123.22mm tall.

The hole at the top is 2.5mm thick, is 29mm wide and, 13.5mm deep. The picture frame was held in by friction but I added some extra super glue to provide more holding power.

I printed in PLA using Bambu's 0.20 Strong Profile.