For each clamp the following is needed:
2x M4 nuts
2x M4x18 or M4x20 pan-head or cheese head screw.
1x Drywall/wood/ “whatever surface you are trying to mount it to”-screw

Printed in PETG, 0.2mm layers, little bit of support for the screw holes could make them a bit cleaner, but not really needed.

The top part should be printed a bit sunk, the slight angles at the screw holes look nice, but are the not worth the hassle during printing.