Cable/wire retention clip.
Mounting options:
1. Screw mount to surface using both holes. Locks cable in place.
2. Screw mount just the back side and snap the cable into place.
3. Double-sided tape to attach to the surface.

Assorted sizes. Diameters: 
3.2 mm / 1/8"
3.5 mm
4.0 mm
4.5 mm
5.0 mm
6.0 mm / 1/4"
8.0 mm

Mounting hole: 3 mm / #6 wood screw
Print recommendations: print on it's side, with outer brim.

If it works for you, please Like and post a Make with photo for others to see.