The mavic 700c presta inner tube is the perfect replacement if you ever find yourself with a flat tyre the tube has been constructed from a standard butyl rubber and it39s 083mm thick so it won39t add any unnecessary weight to your bike these road inner tubes have been designed to fit 700 x 21 25c tyres mavic 700c presta inner tube features thick 083mm butyl rubber designed to fit 700 x 21 25c tyres 48mm presta valave for easy inflation weight 97g approx