Since it runs on a battery (not included with this version), the Makita DGA504ZJ even allows you to grind in places without a power supply. The compact 18-volt angle grinder is just as efficient as any wired version, though. The automatic speed control ensures that you can perform any task with the right amount of power. As a result, you'll keep a constant RPM, even under heavy load, like when you're grinding stone. The restart and overload protections let you work safely, as does the mechanism that turns the grinder off when the grinding disc is jammed. The brushless motor and the proper protection against any intruding dust and moisture make the DGA504ZJ a durable angle grinder suitable for regular, intensive use.