HTP America's battery operated tungsten grinder features portability and wide range of motion. It has six speeds to choose from, ranging from 8,000 to 30,000 rpm with a digital display, and puts a 22.5 degree point on your tungsten electrode. Also comes as an adjustable angle model with the bonus of adjusting the angle, or the point of the tungsten, from 10 to 30 degrees. Both of these tools include a 1/16", 3/32" and 1/8" collets, all enclosed in a convenient carrying case with battery charger, and are available as 110V models as well.