The length of which tool is determined by the overall length of its shaft and blade excluding the handle?

• A. Screwdriver
• B. Hex wrench
• C. Crow foot wrench
• D. Open end wrench

Answer: (A)

The length being described is the part that actually engages the work. For a screwdriver, that working portion is the shaft and blade (the tip that fits into the screw). The handle is just a grip, so it isn’t counted when we specify blade or shaft length. That’s why screwdrivers are described by the length of their shaft and blade, excluding the handle.

The other tools don’t fit this way of measuring. They don’t have a separate blade or shaft portion whose length is specified apart from the handle, so their length is typically considered as the overall tool length or by the size of the head, not by a blade length.