Disc Tumbler Lock

A disc tumbler lock or Abloy Disklock is a lock composed of slotted rotating detainer discs. A specially cut key rotates these discs like the tumblers of a safe to align the slots, allowing the sidebar to drop into the slots, thus opening the lock. Unlike a wafer tumbler lock or a pin tumbler lock, this mechanism does not use springs. From a security standpoint, the disc tumbler lock cannot be bumped. Because they do not contain springs, they are better suited for areas with harsh conditions and are often used at outdoor locations like railroad and public utility installations.

Disk tumblers are difficult to pick and are sold as "high security" locks. Picking the lock is not impossible, but requires a lot of time, a dedicated, professionally made tool and special expertise. This level of difficulty tends to drive attention to alternative methods of gaining entry. The locking mechanism can be disabled destructively by drilling into the lock to destroy the sidebar. Anti-drilling plates can be installed to prevent this.

In areas of the world where this type of lock has historically been rare or unknown, the term "disc tumbler lock" is sometimes mistakingly used to refer to wafer tumbler locks, which are much less secure and are commonly found on desks and file cabinets.

The lock was invented by Emil Henriksson in 1907 and manufactured by Abloy. Another popular brand in Malaysia is Solex. ABUS manufactures padlocks and cycle locks employing disc tumbler cylinders in their Plus line.