Complete specifications: Insert Brass Nuts Set includes 345 insert nuts with sizes of M2, M2.5, M3, M4, M5, and M6 internal threads. It can adapt to a variety of workpieces. Function: Our Hot Melt Knurled Threads can be used to modify your 3D printer parts, providing a reliable method for fastening parts in 3D Printing projects. Stable connection: Heat Embedment Copper Nuts opposite spiral knurled nuts provide a balanced high tightening torque, ensuring a stable connection. The heat-set insert can be seamlessly installed on PP parts, resist torque, and stop pull out. Performance: Insert Embedment Nuts are made of brass, have good thermal conductivity, are resistant to breakage, are not easy to deform, and can be used for a long time. Applicable: Insert Brass Nuts Set is suitable for thermoplastics, including PLA, PETG, PP, and can be applied to 3D printers, electric molding machines, automotive PP shell, and laptop computer molds. Specification: Material: Brass Size Chart: Packing size: 25cmx15cmx2cm/9.84inchx5.91inchx0.79inch Package Includes: 30 M2xD3xL2.5, 30 M2xD3xL3, 30 M2xD3xL4, 30 M2.5D3.5xL4, 30 M2.5xD3.5xL5, 30 M3xD5xL3, 30 M3xD5xL4, 30 M3D5xL5, 25 M4xD6xL4, 25 M4xD6xL6, 25 M4xD6xL8, 10 M5xD7xL7, 10 M5xD7xL9, 5 M6xD9xL8, 5 M6xD9xL9