M4 Short Threaded Inserts for Your 3D Printed Parts: The ruthex threaded nuts can be subsequently embedded in parts from 3D printers such as Anycubic, Creality, or Prusa using heat or ultrasound. By applying heat with a soldering iron or ultrasound, the inserts can be easily embedded into a blind or through hole. Secure hold with easy application: Thanks to the geometry of the threaded sleeve, it holds firmly in the printed part. The opposing spiral knurled nuts provide a balanced high tightening and loosening torque as well as a high clamping force. The guiding feature simplifies the insertion process significantly. Stable & durable screw threads: The inserts with internal threads are made from high-quality brass, ensuring optimal corrosion resistance and thermal conductivity. This makes each insert usable in the long term and easy to install. The reusability of the screw threads is also possible by carefully removing them from the printed part when they are no longer needed. Suitable for various plastics: The inserts are designed for all thermoplastic materials. The knurled nuts hold securely in PLA, PETG, ABS, PPS, PP, and many more. Once the plastic of the part cools and hardens around the brass sleeve, the internal threaded sleeve is firmly anchored. Practical Threaded Insert Set: The ruthex threaded insert set RX-M4Sx4.0 consists of 50 pieces of press nuts with M4 internal threads and a length of 4.0 mm. The threaded sleeves can be installed using ultrasound and heat embedding.