Downhill(DH) is, in the most general sense, riding mountain bikes downhill. The rider commonly travels to the point of descent by other means than cycling, such as a ski lift or automobile, as the weight of the downhill mountain bike often precludes any serious climbing. Downhill specific bikes are universally equipped with front and rear suspension, large disc brakes, and use heavier frame tubing than other mountain bikes. Because of their extremely steep terrain (often located in summer at ski resorts), downhill courses are one of the most extreme and dangerous venues for mountain biking. They include large jumps (up to and including 12 meters (40feet)), drops of 3+ meters (10+ feet), and are generally rough and steep top to bottom. To negotiate these obstacles at race speed, racers must possess a unique combination of total body strength, aerobic and anaerobic fitness, and mental control. Minimum body protection in a true downhill setting is knee pads and a full face helmet with goggles, although riders and racers commonly sport full body suits to protect themselves. Downhill bikes now weigh around 16 20 kilos (35 45lbs), while professional downhill mountain bikes can weigh as little as 15 kilos (33lbs), fully equipped with custom carbon fibre parts, air suspension, tubeless tires and more. Downhill frames get anywhere from 170 250 millimeters (7 to 10inches) of travel and are usually mounted with a 200 millimeter (8inch) travel dual crown fork.