The upper and lower hollow design facilitates heat dissipation during flight The copper pillars are fixed and stable without shaking and the cover protects the image transmission The servo needs to be purchased separately It is recommended to choose a metal servo of 8 5 12g such as EМАХ ЕS08AII 12gSpecification Brand QY3DItem Name Single Axis Servo Gimbal for 0304 Snail Dual Antenna Video Transmission SystemColor BlackMaterials PETG CF TPUWeight 17 5gDimensions 80 50 27mmCompatible with MG90S ServoPackage included 1 x Single Axis Servo Gimbal for DJIO3 DJI O4 Walksnail 19mm Dual Antenna Video Transmission SystemNote This product does not come with a screw set the included screws are intended for servo installation only Its lens mounting hole is made of flexible TPU with a standard width of 20mm and can also accommodate lenses of 19mm or 21mm