Because of their small size and lightweight, air ratchets are the ideal tool to use when you need to operate on nuts and bolts in confined areas.
They’re pretty simple to hold for extended periods. This makes them ideal for the kind of mechanic who works for eight to ten hours at a time.
Compared to air ratchets, impact wrenches are noticeably larger and thicker due to their more robust construction. If you need something with more torque, an impact wrench is your winner.