Water Pump Pliers are commonly used for turning & holding nuts & bolts, gripping irregularly shaped objects, holding pipes etc. They hold all kinds of items with larger diameter too, regardless of whether they are round, square or hexagonal. Pliers have serrated jaws set at 45 degree from the handles. The lower jaw can be moved to 7 different positions by sliding along a tracking section under the upper jaw. An advantage of this design is that pliers can adjust to a number of sizes without the distance in the handle growing wider.