The hex nut on the shank of these bridge reamers holds the reamer securely in place in tools that have a square drive, such as impact wrenches. Hex nut shank bridge reamers are suitable for applications where the reamer will be used in a power tool that is being operated at a high location and the operator wants to make sure the reamer won't come loose in the tool. Bridge reamers enlarge, debur, and finish holes in structural materials and have tapered flutes that ease the tool's entry into rough-cut or misaligned holes.Bridge reamers are installed in a compatible power tool to enlarge, debur, and finish holes in structural materials to a specific size. The reamers have tapered flutes that ease the tool's entry into rough-cut or misaligned holes. Also called construction, alignment, and car reamers, they are designed for reaming difficult-to-machine materials such as iron and structural steel in metalworking applications where extreme precision is not required. Bridge reamers are commonly used to ream rivet holes in parts for automobiles, bridges, rail cars, ships, and pressure vessels.