The Delta 7 Sports Arantix Mountain Bike features an IsoTruss carbon fiber frame. What the hell is that you ask? Well it's a frame made of hand-woven carbon fiber strands that are then wrapped in Kevlar and baked. Each one has over 1,672 feet of carbon fiber and takes over 300 hours to build. The resulting pyramidal structure of the frame makes it not only rugged but light -- a measly 2.75 pounds.