The revolutionary Schwalbe Pro Core 27.5"/650b Tube Set means that you can distribute the air pressure in the tire over two chambers for maximum versatility & control throughout your rides. In the outer chamber, the air pressure is extremely low, the perfect choice for off-road performance, while the inner chamber which sits directly on the rim features high pressure to dramatically reduce the risk pinch flats. With a simple turn, you select the chamber into which air is to be pumped. Race proven in downhill & enduro events, the innovative Schwalbe Pro Core tube set pulls together a myriad of high end features to completely re-invent your riding experience.