These Self-Tapping Locking Screws are available in multiple diameter and length options to meet different surgical fixation needs. The listed sizes range from 3.5 mm to 4.0 mm in diameter and 12 mm to 16 mm in length. They are designed to create their own threads in pre-drilled holes and lock securely into the implant, ensuring strong fixation, reduced loosening, and long-term spinal stability.