Makita's 4-1/2 in angle grinder combines 7.5 A power with comfort and motor-protection features for longer-lasting industrial performance. The 9557PB angle grinder delivers 11,000 rpm, with soft start for smooth start-ups. The angle grinder also features a range of durability features including labyrinth construction which seals and protects the motor and bearings from dust and debris for longer tool life, as well as a protective zig-zig varnish engineered to seal the armature from dust and debris. Ease-of-use features include an extra-large paddle switch for comfortable operation and a lock-on or off feature for continuous operation. The 9557PB weighs only 4.5 lb with a side handle that can be easily installed on either side of the tool. In addition, the tool-less wheel guard adjustment provides easy clamping. This grinder also has an ac or dc switch for use with alternative-power sources. The 9557PB is a versatile and powerful grinder engineered for cutting, grinding and polishing applications.