Deep picture frame

Adjusted the original (https://www.thingiverse.com/thing:2693157) to fit my tastes a bit more and to allow me to use it for a baby foot cast. Made a backside to keep the cast in place (used glue connect the pieces). Have added some nut traps which should fit most square m3 nuts, to make it easy to connect the frame to other things (such as a stand) via m3 bolts.