What is the name of the socket handle that has a gear and lever mechanism for rapid fastener removal or installation?

The name of the socket handle that features a gear and lever mechanism for rapid fastener removal or installation is known as a ratchet handle. This tool is designed to allow the user to turn a fastener quickly in one direction while the handle can be pushed back to its original position without needing to remove the socket from the fastener. The internal gear system enables the ratchet to engage and disengage, making it versatile for tightening and loosening bolts and nuts efficiently. This mechanism is especially valuable in tight spaces or when dealing with fasteners that require quick adjustments.

The other tools mentioned serve different purposes. A torque wrench is specifically designed to apply a precise amount of torque to a fastener ensuring proper tension, while a breaker bar is a long-handled tool used for loosening very tight fasteners, providing more leverage but without the quick action of a ratchet. An extension bar is an accessory that provides extra reach for sockets but does not incorporate any mechanism for rapid operation.