Zipp Tangente Clincher Tires Zipp Clincher Road Tire 700x21 Aramid Bead Zipp Tire Breakthough! New design will save you 1-3 watts, or up to 9 seconds over 40km. The new Tangente tire. Faster. Tougher. Stronger. Just like you. ISO Diameter: 622 ISO Width: 21 mm PSI: 110- 120 PSI 290 tpi casing