THE HONEYWELL MS7520A2007 Damper Actuator, Spring RETURN, 175 LB-IN, (0)2-10VDC & FLOATING Control, 24 VAC +/-20%, 50/60 HZ, 24 VDC (S20010); S20 Series Spring Return Direct Coupled Actuator, 24Vac, 0/2-10 Vdc, 4-20Ma with 500 Ohm Resistor, On/Off, SPDT, Floating Control Signal, 90 Second Nominal Driving Time, 20 Second Maximum Spring Return, 175 Lb-In Torque, 95 ± 3 Degree Rotational Stroke, Nema 2 Rated, Manual Operation Crank, 3/8″-1.06″ Round or 3/8″-11/16″ Square Damper Shafts, Self Centering Clamping Adapter, 5-95% RH Non Condensing Operating Humidity Range, -40-140 Degree Temperature Range