Time-delay combination locks

A time-delay combination lock is most commonly a digital, electronic combination lock equipped with a delay timer that delays the unlocking of the lock by a user-definable delay period, usually less than one hour. Unlike the time lock, which unlocks at a preset time (as in the case of a bank vault), time-delay locks operate each time the safe is unlocked, but the operator must wait for the set delay period to elapse before the lock can be opened. Time delay safes are most commonly used in businesses with high cash transactions.^[1] They are used in some banks including Nationwide, HSBC, Barclays, and Halifax.