This shows a lock being bumped that has
Lock Bumping Solution added!
The bump key has a distinct look to it. Lock bumping keys are filed down to create little metal spikes which look like shark teeth on the key. When the key is whacked or hit by the lock bumping hammer it then pushes up all the pins at the same time for a split second. When pressure is applied for this split second all the pins are above the tumbler which enables the tumbler to then turn. The hitting or banging of the key with a lock bumping hammer is where the term "lock bumping" comes from.
Lock Bumping keys are used legitimately by locksmiths and therefore legally available. In the hands of thieves they can be used as master keys to open any number of locks quickly and with minor disturbance. Bump keys will open almost any cylinder lock in the country and as around 68% of all homes are filled with the cylinder locks chances are thieves can get into your home.