This is Micro Swiss All Metal Hotend Kit for Wanhao Duplicator 6 with the following improvements: slotted clamping system. No screw to the thing and damage to the thermal pipe. Significantly better heat transfer (this is a big !!!) Easier to disassemble and adjust Precise control of the bore diameter. Fits: WANHAO Duplicator 6 Monoprice Maker Ultimate 3D Printer Micro Swiss All Metal Hotend Kit Features: This upgrade includes a modified thermal insulation pipe and a modified nozzle with modified cooling block. Thermal insulation pipe consists of 2 different materials. The lower thermal break is made of stainless steel and the colder top is made of aluminium. Stainless steel has been used for thermal breakage because it provides low thermal conductivity and aluminum has been used for the upper part because it has much better thermal conductivity to carry any heat away from the filament. All metal hotend can be printed at much higher temperature than possible with original PTFE lined. Another advantage of an all-metallic design is a more uniform sound chamber control. During the slow extrusion speed, in the PTFE drawn hotend the transition zone from solid to molten plastic tends to sneak upwards to produce more rigorous prints. With all metal constructions, a transition zone is always constant, which is located directly at the heat. With a fast extrusion speed, the PTFE tube does not have enough thermal conductivity to melt the entire plastic. For original extruders, depending on the nozzle size, there is a limit of approx. 60 mm/s. All metal hove solves this problem, plastic is surrounded by thermally conductive nozzle over its entire length. Aperture size 0.4mm kit includes 1 plated brass wear resistant nozzle 1 thermal tube 1 slot cooling block