Traditional high security yale nightlatch with convenient lever handle to operate lock inside the property Automatic Deadlock is engaged when you close the door for instant security and latch bolt can be held back temporarily with snib button Includes Yale rim cylinder operated by key from the outside with standard security components Internal nightlatch handle can be locked from the inside with a key, ideal for use with wooden doors with large glazed panels Supplied with 2 standard Yale keys and fixing pack Anti-card slip protection, prevents your lock from being vulnerable to this specialist technique that only requires a credit card sized piece of plastic