Description: Size and Shape: rounded tube with 6mm outside diameter, 4mm inner diameter, 500mm overall length. Lightweight: strong as metal but only one fifth in weight, corrosion-resistant and heat-resisting. Smooth Surface: made of high tensile carbon fiber, glossy surface with a polishing finish. Application: carbon fiber wing tube is used for racing drones, RC helicopter wing, RC airplanes and RC sailboats, kite spars. Features:Tube Shape: Circular PipeOutside Diameter: 6mmInner Diameter: 4mmOverall Length: 500mmFinish Type: Polishing Package Content:1 x Carbon Fiber Tube