High quality metal geared servo with half aluminium case for extra strength. Model: WK-DMM130 Torque: 13.2kg-cm at 4.8V / 14.5kg-cm at 6.0V Speed: 0.15sec/60 at 4.8V / 0.13sec/60 at 6.0V Weight: 58g Dimension: 40*20*40mm (LxWxH) Motor: DC Motor Gear: Metal Bearing: Dual Ball Bearings