This Prusa Nozzle Brass is a full metal nozzle that is equipped with a heatbreak. By eliminating the use of PTFE tubes, the general reliability of the 3D printer is increased and it is easier to change nozzles. This product is 0.8 mm and suitable for the MK4, XL, MK3.9, MK4S, MK3.9S and the CORE One 3D printers from Prusa.