A Wrench is a device which is used to provide a mechanical advantage while applying torque to turn bolts or the things which can interface with a wrench. It is also known as Spannar.
The most common type of Spannars are Open ended spanner and Ring spanner or wrench.
There are various types of wrenches available in the market such as Pipe wrench, Aluminum pipe wrench, Chain tongs, Adjustable wrench, Hydrant wrench etc.
Chromium-Vanadium alloys tool steels are used to produce higher quality wrenches which are drop forged. They are also coated with chrome to avoide corrosion.