Since 2000, Philadelphia-based CHRISTINI AWD Bikes has hand-welded and fabricated custom bicycles and e-bikes around its patented mechanical all-wheel-drive system, which sends power to the front wheel when the rear loses traction. The company builds each bike to order in its own U.S. factory rather than merely assembling imported frames, and its machines have crossed Antarctica, Greenland, and the Yukon while reaching riders in more than 35 countries. CHRISTINI also supplies AWD e-bikes for U.S. and allied Special Forces units in several countries.