Flat knob with lever printed in place. It has hole for m4 nut. It's my try for minimalistic functional design. Model is oriented to print. No need for supports. It's designed to print with 0.2mm layer height (bridges in nut part).

Added another version, with more hidden lever in the outline.

One more, minimal filament used, only 20mm wide.

If you want same finish as minimal knob, use Hilbert curves infill on bottom layer and set 1 perimeter on layers from 0 to 0,2.