This is a simple gridfinity holder an angle gauge set. It uses a 2x3 grid.  (I laser engraved the angles on the gauges for better visibility)

The model shown is printed with eSun PLA+ Bone White for the base and a 1.5mm lip at the top using Polymaker PLA Pro Metallic Chrome for a contrasting accent.  This was done with a layer height modifier for the last 1.5mm.

Here's a list of what's used in the holder:

• Accusize Angle Gauge Set (the one I used)
• HFS Angle Gauge Set (cheaper alternative)