I buy my tubes in bulk so I don't have to go to the store all the time... These tubes came in quickly and are absolutely great! They have an inner fluid that helps prevent flats, and the bumps also seal punctures as well! I use thick wire bead tires, so I haven't had a problem with any punctures yet. These tubes are strong, reliable, and light given for their purpose... They aren't the lightest out there, but compared to other DH tubes I've used, these are way lighter and hold up just as well, if not better than my previous DH tubes. I got a price match, so I got these tubes for a killer deal as well! I ride DH and DJ pretty hard, so I abuse my tires and tubes.