No flats yellow gel self sealing inner tube high quality mountain bike inner tubes prefilled with joes yellow gel inner tube sealant with fiber gel technology prevents flats by instantly sealing punctures in the tread area of the tire up to 3mm contains micro fibers to prevent and repair punctures non toxic and long lasting features if you get a puncture always spin the wheel to distribute the sealant if spinning does not work find the hole in turn the wheel so the hole will face the g