A digital multimeter or DMM is one of the most useful tools that you can have around the house.  The device is designed to measure a variety of electrical matters, and is invaluable for many household and automotive repair processes.
 
Whether you are installing a new light switch or electrical outlet in your home, or testing your spark plugs or alternator in the car, a digital multimeter will prove itself to be a valuable addition to your toolkit, and can measure everything from whether there is a current through an item caused by a loose wire through to whether a battery is charging properly.

Perhaps the best known company who makes digital multimeters is called Fluke.  Based in Everett, Washington, Fluke has been producing high quality scientific and precision measuring equipment for nearly 60 years.  The company was one of the originators of the concepts behind the Digital Multimeter, and to this day produces some of the best models around, making them the first choice for most professionals looking for high quality and robust devices that offer excellent accuracy, and are hard wearing enough to last for years in even the most tricky conditions.

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