Accuracy rating: C7 Rolled Ball Screw. Industrial Part No: SFU1204-1000mm. Diameter of Ball Screw Rod: Ø12mm Lead: 4mm. Ball diameter Ø2.381mm. Flange Diameter: Ø42mm. Flange Barrel: Ø22mm. Flange flats (surface to surface):32mm. Length of nut: 35mm