Makita 9564 4-1/2-Inch Industrial Angle Grinder 9.5 AMP motor (10,500 RPM) for continuous operation - even in the most harsh working conditions. Exclusive labyrinth construction and protective zig-zag varnish seals the motor from contamination from dust and debris. SJS "Super Joint System" helps prevent gear damage from sudden stops and binding. Larger and improved carbon brush material for longer tool life.