Some of the PCBs and modules I use don't have mounting holes, or have holes close to components with the risk of damage or shorts, have holes which are too small, or have edge connectors. This mount supports the PCB approximately 9mm above the surface below.

The design is 15mm x 15mm x 10mm The slot is 2.5 mm x 2.5 mm deep. The hole is M3 clearance.

ADDED: .stl file for a PCB Mount/Bracket 16mm. This supports a PCB 16mm above the baseboard. In my current project this is the same height as the output of an attenuator with 'N' to SMA adaptor. Shown in the attached photograph. Photo somewhat compressed by Thingiverse! (Attenuator support is https://www.thingiverse.com/thing:4001471 )