Air Die Grinder, available collet in 1/8" and 1/4", free speed 22,000RPM... Free speed:22,000RPMAverage air consumption (25%): 4SCFMCollet: 1/8", 1/4"; 3mm, 6mmExhaust: Rear 360oLength:165mmWeight: 0.62Kg, 1.37LbsAir pressure:90psi, 6.3kg/cm2Air inlet:1/4" Air Die Grinder