With a 1.50 horsepower air motor that delivers a no-load operating speed of 12000 rpm, and a 5/8"-11 threaded spindle, the new MP-2511 is the most powerful grinder available for heavy-duty needs. The MP-2511 is designed to be light and sturdy for the most effective metal removal, and is best suited for cleaning castings, removing fins and grinding welds. A built–in lubricator and automatic governor provide lifelong dependability.* Wheel Capacity Cone Wheel * Speed 12000 rpm * Spindle Thread 5/8''-11 * Maximum HP 1.50 * Length 13-1/2'' * Weight 4.00 lbs. * Air Inlet Thread 1/4'' * Avg. Air Consumption 11.9 cfm