This item inculdes : 1 PC Closed loop Stepper Motor Nema23 57HBM20-1000 4A 210N-cm(300oz-in) 1 PC Mactching Driver WTSS570 Technical Specifications Part No.: 57HBM20-1000 Frame Size: NEMA34 Step Angle: 1.8 degree Voltage: 1.76V Current: 4.0A/phase Resistance: 0.44 Ohm/phase Inductance: 2 mH/phase Holding torque: 2.1N.m 300oz-in Rotor inertia: 480g-cm2 Number of wire leads: 4 Weight: 2 kg Length: 101mm