Challenge's Criterium Seta Extra is the choice of the pros. Countless victories and podiums have been been won thanks to its supple, hand-made silk casing. It makes the tires race-day light, fast, and strong. This exceptional tire has a center tread that rolls quickly with a grippy side tread for excellent cornering. There's puncture protection under the tread, too. You also get a latex tube. Latex tubes are lighter, thinner and more flexible than butyl tubes, increasing your comfort, lowering rolling resistance, and helping to prevent flats, too.