This is the KST DS215MG Micro Digital Servo, for Cyclic and Tail use. Looking for speed in a micro package? The KST DS215MG is lightning fast, high voltage compatible and comes in a beautiful aluminum case. Power comes via a coreless motor, running on silky smooth bearings with all metal gears. For the ultimate in speed and accuracy, turn to the DS215MG for your demanding needs. V3.0 As time has progressed, KST has done additional development on the gear train of the 215 servo, and changed the servo gear material used to Stainless Steel, from Aluminum. This means that the metal gear train will be much more durable than previous versions, improving durability greatly. Features: Micro size aluminum case Full metal gears Dual ball bearings HV compatible Lightning fast Coreless motor Specifications: Operating Voltage:6-7.4V Size:23x12x27.5mm Torque: 3.10kg.cm @ 6.0V; 3.70kg.cm @ 7.4V Speed: 0.06sec/60 @ 6.0V; 0.05sec/60 @ 7.4V Weight:20g Working Frequency: 1520us/333Hz, 800us - 2200us Motor:Coreless Ball Bearing: 2BB