Usage Tips:Features: The UM3 extruder nozzles are through long-term testing to solve the problem of plugging and missing materials to the greatest extent. With low thermal conductivity, resistant to corrosion, high abrasion resistance. Also these 3D printer extruder nozzles has impressive toughness and hardness, high temperature resistance. The inner wall of the UM3 nozzles is smooth and has no burrs, it's viscosity coefficient is small, and extruder nozzle diameter error is less than 0.02 mm, providing you an accurate and smooth extrusion 4pcs set to facilitate your timely replacement, achieving quality printing Specifications: Material: Brass Nozzle Diameter :0.4mm Color: Gold Nozzle Length:3mm/0.11in Type: for Ultimaker3 Um3 Brass Nozzles Quantity:4pcs Note: When disassembling, heat to over 200 before disassembling Due to the problems of lighting effects and shooting angles, there will be certain tolerances in the product, please understand. Please allow 0-1cm error due to the manual measurment. Package includes: 1 Set/4Pcs UM3 Nozzles