JET 402121 - .6 HP 1/4" 3" Extended Air Die Grinder – Heavy DutyPowerful .6 horsepower motorFront exhaust, compact motor housingMotor shaft features ball bearings front and back, and motor end plates are made from durable die cast aluminum metal for maximum life and performanceFeatures a special "coupling nut" which connects the motor to the extended shaft, for vibration absorption and easy dismantling during repairsCoupler features a third ball bearing for longest life and smooth operation