This is a strain relief for the wires and the PTFE tube attached to the extruder of the FLSun Cube 3D printer. It is installed using the bolts of 2 of the linear bearing holders. The M4x16 bolts will need to be replaced by M4x20 bolts. A zip tie is used to attach the wires and the PTFE tube.
No support is required to print this part. 20% infill is sufficient.
A tougher version of it is available at https://www.thingiverse.com/thing:3772780 .