Impact Driver +
![Impact Driver](https://files.ozbargain.com.au/t/37/63737.jpg?h=e03ab1d8)
A manual impact driver is a tool that delivers a strong, sudden rotational force and forward thrust when struck on the back with a hammer. It is often used by mechanics to loosen larger screws (bolts) and nuts that are corrosively "frozen" or over-torqued. The direction can also be reversed for situations where screws have to be tightened with torque greater than a screwdriver can reasonably provide.