What’s a 999 Key?

Bump keys circumvent locks and act as a “master key” for opening most locks. All grooves on a bump key have been shaved down to the deepest possible depth making them almost universal. The name “bump” key comes from the final step in operating the key. After the key has been inserted, the back should be bumped hard enough to unlock the lock.
When done correctly, bump keys are effective in nearly 90 percent of all cylinder-type locks produced today. Their use can go undetected, allowing homes to be broken into without signs of forced entry. Most locks can be bumped open in under 30 seconds without leaving noticeable evidence.
Bump keys are increasingly used in burglaries because they provide quick, covert access to buildings. They do not work on car locks since those use different mechanisms. A bump key made for one lock brand, such as Kwikset, can open any lock of that brand that it fits into. Bump keys usually don’t damage locks.

Bump keys exploit the mechanical nature of pin-tumbler locks by applying targeted force to manipulate the pins and grant unauthorized access. They specifically target pin-tumbler locks installed in buildings. Bump keys are affordable and their use is widespread.
Specially crafted bump keys can quickly open locks without visible damage or signs of tampering. The bumping technique for opening locks has been used by locksmiths for decades though most lock owners are unaware of its ease and simplicity.

Bump keys forcibly bypass lock mechanisms to allow locksmiths to easily open storage and buildings after disasters. Called "999 keys", their ridges are cut to the maximum depth allowed by key cutters.