Kevlar is well known as the material from which bullet-proof vests and body armor is made. But it can be used in many more applications, such as bicycle tires, yacht sails, ropes, and brake pads. It can do this because, despite it being a fiber, it has an extremely high stength-to-weight ratio, often quoted as being 5 times stronger than an equal weight of steel. It is actually a trademark of the chemical company DuPont, who first synthesized it in 1965.