FD-RD Thread Rolling Dies for Tube Nuts: High-precision grinding ensures exceptional thread forming. Crafted from durable SKD11, DC53, or D2 steel, hardened to 58-62 HRC for a lifespan exceeding 50,000 pieces. Compatible with all thread rolling machines, supporting Metric, UNC, UNF, and BSW threads with customizable angles. Available in diameters 45-260mm, re-grindable for extended use.