Carbine Doncaster Vestibule Clutching Lever SetCarbine 7000 Series Doncaster Vestibule Lever Set Clutching 70mm Backset. Clutching Stops forceful damage to the lock. Function Outside Opened by key only. The outside lever always remains rigid Inside Opened by lever at all times Optional choice of a standard or clutching function, the clutching model features an operation where the outside handle still moves when locked, ideally to prevent lever damage from forced entry. Additional Information Fire