Manipulation is often the preferred choice in lost-combination lockouts, since it requires no repairs or damage, but can be time consuming for an operator, the specific difficulty depends on the unique wheel shapes and where the gates rest in relation to them. Wheels made from lightweight materials will reduce valuable sensory feedback, but are mainly used for improved resistance against radiographic attacks. These group 1 locks were developed in response to group 2 lock manipulation.

More sophisticated locks use advanced mechanics to reduce any feedback a technician could use to identify a combination. To find the combination the operator uses the lock against itself by measuring internal movements with the dial numbers. Mechanical safe locks are manipulated primarily by feel and vision, with sound helping the process occasionally. These devices mimic human manipulation by 'feeling' and measuring mechanical movement within the lock. When used in cooperation with each other the two technologies closely mimic manual manipulation. These new devices use more advanced robotics and more advanced software. In recent years faster devices have been engineered for lock bypass. These auto-dialer machines are known to take 24 hours or more to reach the correct combination. Similar damage free bypass can also be completed by a computerized auto-dialer or manipulation robot. Once the combination is recovered it may be reused to open the safe lock. Manipulation will unlock a safe and recover its combination. Manipulation procedures can vary, but they all rely on exploiting the presence of mechanical imperfections in the lock.

These professionals manually manipulate the lock in order to obtain the combination one number at a time.

Expert practitioners of this art can open locks with speed and consistency. While manipulation of combination locks is usually performed on Group 2 locks, many Group 1 locks are susceptible to manipulation. Manipulation only requires fingers, eyes, and proper technique though it is a skill that takes years to develop and decades to master. It is a damage free combination recovery method, and a well known surreptitious bypass technique. Lock manipulation is the stereotypical safe cracking technique commonly portrayed in movies.

Default combination for meilink safe