You are at your best when you are in your PRIME. You feel confident because you know you are in your Best condition. Conquer the mountains and trails with PRIME TR Rims! Disposing of the tube means there is less or no contact/friction at all between tube and tire and therefore less rolling force is pressured when the tire rolls over ground and other trails. A big advantage for all those who like to ride for a long ride that suits your taste, also built for hard rides and all mountain for your preferences.