There are many advantages to using a 5 lever lock. A 5 lever lock protects against drilling, lock pick, and sawing. Each lock has a number of safety features that make the 5 lever lock the standard in Britain for exterior door protection. In fact, you cannot get a homeowner's insurance policy in Britain without having a 5 lever lock installed on all exterior doors.
What is a 5 Lever Lock?
A 5 lever lock is a lock that uses a standard key, and consists of 5 different levers inside the lock itself that must be turned in order for the lock to be opened. The number of levers is what makes it so difficult for the 5 lever lock to be picked. The levers are reinforced with what is called a curtain, that helps cover access to the levers to prevent a lock pick from getting to them. The levers cannot be reached unless the curtain is turned, which can only be done by the key.
Besides the curtain and number of levers, the 5 lever lock has even more safety features. There are anti-drill plates on both the front and back of the lock, preventing drilling. Finally the bolt head is nearly two inches thick and has two hardened steel roll bars that prevent sawing and drilling of the bolt head. This bolt head also prevents kick ins.