For extending the length of threaded bar. Plated in Trivalent Chromium (Cr3) Zinc Standard metric thread" Thread Dia. mm: M10 Socket Size mm: 17 Height mm: 30.0 Thread Type: Metric Finish: Zinc & Clear Cr3 Material: Carbon Steel Timco Hex Connector Nuts - Zinc (Size M10 - 100 Pieces) in Silver