a simple double coat hook.  The hook is 8mm wide (tall when printing) and the inner diameter of the hook is 20mm. The hooks are spaced vertically 60mm.

The screw holes are 4.5mm with a large countersink. I used 4x16mm screws in the photos. 

The upper screw hole is angled to give clearance for a standard bit holder. It is advised to pre drill the top hole because it is at an angle and the screw might wander when installing.

A standard built plate can fit 16 of these hooks.