The ultimate BMX racing tyre in a larger OS20 sizing. The PowerBlock is designed to efficiently transfer pedal power and other rider inputs into lateral motion. In short, you\'ll roll faster with less wasted energy. This version utilises Tioga\'s thinnest sidewall for maximum suppleness and weight savings. Size for size, the PowerBlock is one of the lightest BMX tyres in the world. The OS20 must be used with specific OS20 frames and rims, however many forks will accept this tyre sizing.