Pump pliers, also known as water pump pliers, are a type of tool that was designed for use in grasping, compressing, holding and applying force to an object. 

These pliers are often used for automotive applications and home plumbing, with the varying jaw width and offset handles combined to make them perfect for loosening or tightening spring-type clamps and water hose connections, which need a fairly wide jaw opening. The extra length of the handles, in combination with how easy it is easy to grasp the tool, provides increased compression force and leverage. 


The main characteristic of these pliers is that the design uses an adjustable fulcrum that enables the jaws to cope with objects of various sizes. The jaws may be able to operate from a closed position to several centimetres apart, depending on the tool size. 

The design of water pump pliers also comes with an elliptical opening that means the pivot can slide along and use any of the channels available in the jaw handles. A tongue or protrusion in the opposite handle can then slide into the chosen channel, allowing the desired space between the plier’s jaws to be maintained. This also means that the user can comfortably compress or grasp objects of different sizes because the handles stay in more or less the same position, which can be very useful for mechanics and plumbers. 


Both plumbers and mechanics need water pump pliers. Pliers can adjust metal parts, cut objects in tight areas such as under sinks or inside car engines, and cut wires. 

They are particularly suited for gripping angular and round parts, even when dealing with larger diameters.

For plumbers, water pump pliers play an important role regarding sanitary installation, and the finer the adjustment they can offer, the greater precision the pliers can be adapted to the size of various objects such as pipes. 


Water pump pliers are usually made from high-carbon steel and may have chrome plating in addition to rubberised handle grips. Some water pump pliers may be made from brass to prevent sparking when needed in explosive atmospheres or when working with objects that contain flammable liquids, such as a car engine. 


The length of the handles determines the sizes of the water pump pliers. These tools can be as short as four inches or as long as 24 inches. Plumbers and mechanics use pliers between six and twelve inches in size. There are angled jaws on water pump pliers, distinguishing them from the common slip joint pliers, with the handles from the jaws between 45 to 60 degrees. This gives an advantage when manoeuvring in tight spaces and allows for greater adjustability. 

Many of the challenges that plumbers and mechanics face can be handled using water pump pliers.