This teflon tube lines the inside of the hot end extruder. There are two sizes that are not interchangeable. Please ensure you select the one that is compatible with the nozzle of your extruder.
Version 1 ONLY complicate with Version 1 Nozzle pictured above. The tube has 3mm outside diameter.
Version 2 is ONLY complicate with Version 2 Nozzle pictured above. The tube has a 4mm outside diameter.