Building a drone, robot, or any project that needs a crazy strong yet incredibly light frame? These carbon fiber tubes are perfect. You get two tubes in this pack. Each one is 1000mm long (about 39.4 inches) with a 12mm outer diameter and a 10mm inner diameter (so a 1mm wall thickness). They're made from full 3K twill weave carbon fiber with a glossy black finish, which looks as awesome as it performs. The strength-to-weight ratio is mind-blowing - they're about a quarter the weight of steel but massively strong and stiff. They're also corrosion-resistant and won't rust. Great for constructing the arms of a hexacopter or quadcopter, creating lightweight pushrods, building model aircraft spars, or any DIY project where you need rigidity without the heft. They can be cut, drilled, and sanded (wear a mask!) to fit your specific needs. Just a heads-up, you'll need your own tools to cut them to size.