【Premium Material】: These female thread insert nuts are made of excellent brass material, which is not easy to break and durable for a long time, has high hardness, corrosion resistance, durability and stability.【Easy to Use】: The insert nuts are threaded inserts for further insertion into 3D printer parts. Using ultrasound or a soldering iron, slotted nuts can be easily embedded into plastic parts. 【Practical Design】: Spiral knurled nuts have superior strength, which ensures balanced high tightening and loosening torque and strong extraction force, and are not easily deformed due to their shape and teeth. 【Wide Applications】: Threaded insert nuts are suitable for injection molding, PCB assembly, electronics and fastening most plastics, such as plastic, PLA, PETG, ABS, PPS, PP, etc. 【Package Contents】: You will receive 220 pieces embedded nuts in size M2/M2.5/M3/M4/M5/M6 in total, enough for your daily use. Threaded insert nuts are commonly used in injection molding for firm fastening.