This is a large binding holder for the binding you put on your quilt. The heart clip will snap on to the holder when not in use. I have had some filament print where it was hard to put the heart on. That was only with the grape Inland Filament. If you have a problem with it printing different on your printer or with the filament you use, then sand the inside of the heart clip to make it fit. I have printed these on my Ender 3 and my bambu X1 Carbon with the same result.