TheConitnentalGrand Prix 4-Season is as effective at racing and general road riding as the venerable Grand Prix 4000s but witha extralayer of Vectran breaker to keep flats at bay during longkilometersof training and racing especially in wet or grittyconidtions. The 4-Season only weighs 5g more than the GP 4000s but give you a little extra peace of mind. Now it is up to you to put thekilometersin.