https://www.vxolinearmotion.com/products/lead-screw-and-nut-assembly/ Lead screw nut assembly from VXO are designed for maintenance-free operation and offer an extended service life. Our lead screw nuts are designed with self-lubricating engineered composite plastic materials, eliminating the need for external lubricants and lead screw coatings. In addition to trapezoidal thread and acme thread, we offer a proprietary high helix design that's asymmetrical to our plastic nuts. This design helps optimize lifetime and offers higher efficiency.