Filament - popular term for any material that can be used in the process of printing in FFF technology. Filament is a thermoplastic material (PLA, ABS, PET, HIPS etc.) in a form of a wire wound on a spool. Tolerance of realisation and protection from moisture (vacuum packing and moisture absorber) are significant factors while choosing a proper filament. Once opened the filament should be stored with a moisture absorber in a dark, dry place.