WTB Nano 2.1 Race Tire Folding Has a round profile, micro-knob design and large supportive casing The elevated centerline tread rolls quickly on asphalt and hardpack, while numerous working-edges trace predictably in "dust on crust" conditions Popular choice for short track XC races, dirt jumping, and urban sessions Folding bead, DNA rubber, lightweight casing 60 tpi 35-65 psi 505 grams