For use with any of our unsprung knob sets or 57mm centre unsprung lever lock handles. Will match any of our aged brass or polished brass products. For matching rebate kit please use product code 91830. Includes an extra strong spring to ensure our weighty knob sets and levers always return correctly. Case Size:109mm (H) x 17mm (T) Case Depth: 76mm Backset: 56mm Centre: 57mm Forend Size: 162mm (L) x 26mm (W)