Rockshox Boxxer World Cup Solo-Air 2013 200mm DH20 Keronite (155901) With 66 World Cup wins the BoXXer is the winningest downhill fork in the history of the sport. RockShox BoXXer is pure racing and w/ its smooth and consistent damper feel of the Mission Control DH in a decadently light Package the Keronite Gray version got even lighter it is the perfect choice for every World Cup track on this planet. Travel: 200mm. Damping: Mission Control DH Rebound: Dual Flow Adjust. Spring: Solo Air. Steerer: 1-1/8 Aluminum. Upper Tubes: 35mm.