This is a small funnel-shaped guide that snaps over a standard M6 PTFE Bowden fitting used for 1.75 mm filament.
The purpose is to make filament loading much easier by providing a wide, smooth entry cone instead of trying to hit the tiny PTFE tube opening.

Just slide the funnel onto the fitting and align the internal hex cavity with the M6 nut shape.
Perfect for printers where filament is loaded “blind” or at an angle.

Model has in print support which can be easily removed with almost no force.