Lightweight: strong as metal but only one fifth in weight, corrosion-resistant and heat-resisting. Carbon fiber pipe fittings and plate Uxcell Carbon Fiber Round Tube 5mm x 3mm x 400mm for RC Airplane Quadcopter 4 Pack Size and Shape: pultrusion rounded tube with 5mm outside diameter, 3mm inner diameter, 400mm overall length. Pultrusion: pultruded tube means that all the fibers are in one direction, which makes it stronger than the woven tube in tension. Lightweight: strong as metal but only one fifth in weight, corrosion... Smooth Surface: made of high tensile and modulus unidirectional carbon fiber. Pultrusion: pultruded tube means that all the fibers are in one direction, which makes it stronger than the woven tube in tension. RC enthusiasts and DIY builders, these uxcell carbon fiber tubes are seriously lightweight yet crazy strong. We're talking 5mm outside diameter with 3mm inner diameter, each tube measures 400mm long, and you get 8 of them in the pack Application: pultruded carbon fiber tube is used for racing drones, RC helicopter wing, RC airplanes and RC sailboats, kite spars. Lightweight Carbon Tubes Carbon Fiber Round Tube 4mm X 3mm X 400mm Carbon Fiber Pultrusion RC Airplane Quadcopter Frame Tube Smooth Surface: made of high tensile and modulus unidirectional carbon fiber, with polishing finish.