Astro Pneumatic's 2181B ONYX 2 pc. Die Grinder Kit includes a 1/4-Inch Medium Die Grinder and an 8pc. Double Cut Carbide Rotary Burr Set. Features of this set includes a lever throttle for feathering control, a rib textured handle which provides a firm grip and a rear exhaust air flow system that directs air away from work surface. Additionally the increased motor size provides more power to make completion of work that much easier.