Features:The MK8 extruder nozzles are through long-term testing to solve the problem of plugging and missing materials to the greatest extent, low thermal conductivity, resistant to corrosion, high abrasion resistance.Also these 3d printer extruder nozzles has impressive toughness and hardness, not only suitable for common 1.75 mm. 3D printer filaments, but also can be applied for printing filaments of carbon fiber, fiberglass, etc.The inner wall of the MK8 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 extrusion15Pcs/30pcs Set sufficient quantity to facilitate your timely replacement, achieving quality printingProvide around nozzles in multiple sizes for different speed/precision combinations to find your ideal fit. Package Includes:15x MK8 Nozzles 0.4mm or 30X MK8 Nozzles 0.4mm Specifications:Specification:13 x 7mmMaterial: Brass Nozzle Precision:0.4mmScrew Thread :M6Input Diameter: 1.75mm note: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. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.