The Euro Cylinder lock can range in security and are now made with a snap resistant core. The lock works by rotating to move a bolt, tumblers and pins, when you insert the key into the lock the key lifts and aligns the pins to free the cylinder to rotate and open or lock the door. You can have a variety of pins, the most common lock being the 5 pin euro cylinder lock. The more pins you have in the lock, the harder it is to gain entry.