Michelin pro4 endurance v2 blue free tubethe michelin pro4 endurance v2 road bike tyre is ideal for sportive riders thanks to a bi compound tread which provides greater puncture protection increased durability and excellent grip pair this with the a1 airstop butyl tube and youve got a winning combo a1 airstop butyl tubes answer the needs of everyday cyclists for economical high quality inner tubes they offer excellent puncture resistance and the consistently high quality for which mich