When there is potential danger to your security or privacy, you have just a fraction of seconds to respond and at this point of time you need high security locks because it would take many steps to get lock it out that means it delays and decrease the moral of the miscreants. We install the deadbolts and deadbolt lock has no spring mechanism. There is a sort of unique puzzle which only correct key can solve.
A single cylinder deadlock will accept a key on one side while Double cylinder locks will accept a key on both sides. This prevents unwanted unlocking of the door by forced access to the interior twist knob (via a nearby window, for example). Double cylinder locks are sometimes banned from areas because they can be difficult to open from the inside and violate fire safety regulations. Some lock manufacturers also have a “lockable” knob: a key is always needed on one side (usually external), and a twist knob can be used on the other (internal), unless a button has been pressed, in which case a key is also needed on the internal side. We install and repair high security locks.