Pin tumbler lock

The first known example of a tumbler lock was found in the ruins of the Palace of Khorsabad built by king Sargon II (721–705 BC.)

These could be lifted, using a key, to a sufficient height to allow the bolt to move and unlock the door.

[2] This wooden lock was one of Egypt's major developments in domestic architecture during classical times.

The keyway often has protruding ledges that serve to prevent the key pins from falling into the plug, and to make the lock more resistant to picking.

With a key properly cut and inserted into the groove on the end of the plug, the pins will rise causing them to align exactly at the shear point.

When the key is not in the lock, the pins straddle the shear point, preventing the plug from rotating.

Commonly pin tumbler locks are found in a cylinder that can be easily unscrewed by a locksmith to facilitate rekeying.

These may make the pin appear to be set when in fact it is still blocking the shear line and preventing the lock from opening.

These and other security pin designs can add delay (increasing the chance of being apprehended) and, by adding complexity, may deter an attacker who does not know how to defeat these countermeasures.

Some security pins as well as different spring designs can also make a bumping attack less likely to succeed, though this may depend on factors such as the degree of variation in bitting height between adjacent cuts in the operating key.

[8][9] Police in the UK have estimated that around 22 million doors throughout the country could be at risk from lock snapping.

development is to build a lock with a front section that snaps off the main body, leaving enough of the mechanism behind to prevent access to the operating latch.

Criminals utilise a small blow torch to target the area of uPVC or composite material surrounding the euro lock and door handle.

The goal once having created the hole is to reach with mole grips deep past any sacrificial lines of an inferior euro cylinder lock.

[citation needed] Cylinders that meet either Sold Secure SS312 Diamond or TS007 3 Star standard will protect against drilling, picking, bumping, snapping,[11] and plug extraction methods of attack.

A common type of pin tumbler lock, of the euro cylinder type
Euro profile locks, an example of a cylinder lock. These are commonly found on uPVC doors and commercial buildings where re-keying doors is common.