ARRIS 16mm Outer Dia. 500mm 3K Roll Wrapped 100% Carbon Fiber Tube 14mm*16mm*500mm Matt Surface (2 PCS) 3K Pure Carbon Fiber, use for RC Quadcopter, Multicopter, Helicopter and Airplanes. Length: 500mm Outer Diameter: 16mm Inner Diameter: 14mm Package Includes: 2 pcs x 14mm*16mm*500mm carbon fiber tube (Matt Surface)