The right tools and test equipment can help improve worker productivity, output quality, and personal safety. Hand tools are tools that are operated manually, without the use of electricity or other external power sources. Examples of hand tools include screwdrivers, saws, pliers, chisels, knives, and wrenches. Power tools are powered by an external power source, such as electricity, batteries, or compressed air. Power drills, power saws, power grinders, and power nailers are common power tools. A cutting tool is used to remove material from a workpiece by applying a shearing force. Cutting tools include drill bits, saw blades, and dies. Cable tools are used to install, maintain, and repair cables. Cable strippers, crimping dies, and cable cutters are examples of cable tools. Test equipment products are used to measure, test, and troubleshoot electrical systems and devices. Electrical power test equipment, network test equipment, and temperature and humidity test equipment are popular types of test equipment.