A simple box with a one way hatch for storing sharps.
Print it with the opening on the bottom, other side will bridge nicely using the built in ribs
No supports needed.

To use simply press the hatch and slide your sharps in, when box is full dispose of it safely along with the sharps.

I printed mine in 0.2 layer height, 0.4 nozzle, 2 walls, 10% infill, using green PETG.