Which tool is primarily used for lock cylinders?

The K tool is designed specifically for manipulating lock cylinders, particularly in forcible entry situations. It is engineered to grasp and turn the core of a lock cylinder, allowing firefighters to gain access to locked areas efficiently and with minimal damage. This tool's unique design includes two prongs that fit inside the lock cylinder, enabling firefighters to pull out the cylinder and unlock the door without needing to destroy the entire locking mechanism.

In contrast, while the axe and haligan tool serve various purposes in firefighting, such as breaking through doors and windows or forcing entry, they are not specialized for working with lock cylinders. The screwdriver can sometimes assist in accessing locks, but its effectiveness is limited compared to the K tool, which is specifically crafted for that task. Therefore, when it comes to efficiently opening locks, the K tool is the best-suited option.