Continental Grand Prix 4000 Bicycle Tire with Black Chili (700x23, Black Transparent) BLACK CHILI- Features Continentals revolutionary Black Chili Compound which reduces rolling resistance by 26% improves grip by 30% and adds 5% more mileage out of your tire. VECTRAN PROTECTION- Reinforcing and matrix fibers made of Vectran are 5X as strong as steel yet still extremely lightweight and abrasion resistant, protecting your tire from punctures more effectively than two layers of Nylon. HANDMADE IN GERMANY-Continental has been hand making their tires since 1871, maintaining the integrity of tradition, while evolving with the most advanced technology. RACING MODEL- The Grand Prix 4000S II is the evolution of Continental's flagship race tire. DISCREET BEAD- Color coordinate to your bike without losing any of the performance of the BlackChili compound.