What tool is used to break loose very tight nuts and bolts?

A breaker bar is specifically designed to provide the necessary leverage to break loose very tight nuts and bolts. It is a long, non-ratcheting bar that allows for extended torque application, making it easier to turn stubborn fasteners that may be rusted or over-tightened. The extended length of the breaker bar amplifies the force applied by the user, thus making it more effective than standard hand tools.

While other tools like a socket wrench can also be used to turn nuts and bolts, they typically do not provide the same level of leverage that a breaker bar does. Torque wrenches are used for applying a specific amount of torque when tightening bolts, rather than breaking them loose. Hinged handles can enhance the capability of specific ratchet tools or wrenches but lack the outright leverage advantage that a breaker bar offers. Therefore, for the task of loosening very tight fasteners, a breaker bar is the most effective and efficiently suited tool.