SG90 Specs: Dimensions: 2211.527mm Operating Speed (4.8V no load): 0.12sec/60 degrees Stall Torque : 1.2kg (4.8V);1.6 kg (6.0V) Operating Voltage: 3.0-7.2 Volts Nylon gears Connector Wire Length: 150MM SG92R Specs: Dimensions: 23x12.2x27mm Output torque: 2.5kg/cm at 4.8V Output speed: 0.1sec/60° 4.8V Working temperature: 0-55 °C Working dead zone: 10us Input voltage: 4.2-6v Internal gear: carbon fibre How it works: Simulation Cable length: 25cm Plug situation: jr SG50 micro servo and a pack of 3 servo arms and screws Weight: 5g Specs: Dimension: 21.511.725.1mm Stall torque: 0.6kg/cm(4.8V) Operating speed:0.1sec/60degree(4.8v) 0.08 sec/60 (6.0V) Operating voltage: 4.8V Temperature range: 0c_ 55c Dead band width: 1us Power Supply: Through External Adapter servo wire length: 15 cm MG90 Specification: Dimensions: 23 x 22 x 12mm Net weight: 17g Package weight: 23g Operating Speed (4.8V no load) : 0.12sec / 60 degrees Stall Torque (4.8V): 10.2oz / in ( >2 kg/cm ) Temperature Range: -30 to +60 Degree C Dead Band Width: 4 usec Operation Voltage: 3.5 - 8.4 Volts MG995 specs: Dimension : 40mm x 19mm x 43mm Original box: NO Net weight: 69g Package weight: 75g Color: Black Operating Speed : 0.17sec / 60 degrees (4.8V no load) Operating Speed : 0.13sec / 60 degrees (6.0V no load) Stall Torque : 13 kg-cm (180.5 oz-in) at 4.8V Stall Torque : 15 kg-cm (208.3 oz-in) at 6V Operation Voltage : 4.8 - 7.2Volts Gear Type: All Metal Gears Connector Wire: Heavy Duty, 11.81" (300mm) MG996R Specs: Dimension : 40mm x 19mm x 43mm Weight : 56g Operating Speed : 0.17sec / 60 degrees (4.8V no load) Operating Speed : 0.13sec / 60 degrees (6.0V no load) Stall Torque : 13 kg-cm (180.5 oz-in) at 4.8V Stall Torque : 15 kg-cm (208.3 oz-in) at 6V Operation Voltage : 4.8 - 7.2Volts Gear Type: All Metal Gears Connector Wire: Heavy Duty, 11.81" (300mm) CYS-S8218 Specs: Digital 6V-7.2V 0.18sec/60a 164g Metal Gear 40KG High Torque Servo. Model No.:CYS-S8218 Weight:164g Size:59.52955.2mm Speed : 0.2sec/60°at (6V) 0.18sec/60°at(7.2V) Torque: 38kg.cm.at (6V) 40kg.cm.at (7.2V)