A 5 Lever mortice deadlocks the highest level of security after a British Standard deadlock. It is important you consult your insurance policy before fitting new locks to any "final exit" doors. Many insurance policies require all final exit doors be fitted with at least one lock that complies with sashlock British Standard BS 3621. If you choose to fit your final exit doors with a 5 lever deadlock, it may be necessary to fit them with a nightlatch that complies with this British Standard as well.
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