The double-bitted key lock is the standard mechanical safe lock found on many safes and fire-resistant cabinets. In practice, a safe with only a key lock is often discouraged: key management remains a risk, and if the key is lost or stolen, an intruder has direct access. For this reason, users generally opt for a code lock or for a dual-locking configuration (key + code) to achieve enhanced security.
Double-bitted key locks are tested and certified according to EN 1300 (classes A, B or C), the European standard for high-security safe locks. They are typically supplied with two keys and often feature a key-retaining mechanism: the key can only be removed when the lock is fully closed.
A key advantage is that a physical key is always required to open the safe. Unlike a code, which can be shared or overheard, a key provides an extra layer of access control. In addition, the lock is simple to use: just insert and turn. Being fully mechanical, it works reliably without electronics or batteries.