This snaps on the top of the extruder where the bowden tube goes in. It keeps the bowden tube a little straighter going in. Takes a little force to install, but you want it tight, you can remove the part above the extruder to install and reinstall after new part is snapped on. See Pictures.

I printed with supports.

As this changes the weight of the tool head, I would recommend running the calibration after installing it.