Features:Brush-less motorReinforced stainless steel final gearHard anodized aluminum gearDual ball bearingsHard servo gear shaftAluminum top caseAluminum heat sink middle caseBlack cableGold plated connectorSerial CompatibleHCS CompatibleSpecifications:Torque: 45.6Kg-cm Speed: 0.12sec/60deg(@7.4V)Torque: 37.3Kg-cm Speed: 0.15sec/60deg(@6.0V)Dimensions: 40.4x37.5x20mm (Standard size)Weight: 77.0gOperating voltage: 6.0~7.4V (Lipo, Life, Ni-MH)