Era BS High Security Nightlatch 40mm Finish: Polished Chrome Body Chrome Cylinder Option:Finish: Polished Chrome Body Chrome Cylinder cracking or shrinking cracking or shrinking For internal or external use which meet the exacting demands of the insurance companies and the police The main lock bolt is 'automatically' deadlocked when the door is closed preventing the main bolt being retracted by a credit card The inside handle can be deadlocked by an anti clockwise turn of the key from the inside so securing the lock against forced entry The bolt can be held in the withdrawn position (only) with the use of the snib feature This product is ideal for solid and glass paneled doors An ergonomic internal locking handle which offers added security against forced entry