Hardin HD-5 Dry Variable Speed Constant Power Polisher / Grinder with Backer Pad (BRHD-5BP). Hardin’s Polisher-Grinder is a favorite among automotive and marine enthusiasts for polishing, grinding and sanding. It combines 7 AMP power and variable speed control. The result is fast and powerful polishing for clearcoat finishes, and more. It can also be easily converted to a grinder. Variable speed control dial enables user to match the speed to the application. Electronic speed control maintains constant speed under load.