Flats happen, but even the most careless pedaler wouldn't use all six of the patches in Park Tool's Vulcanizing Patch Kit in a single ride, right The two oval patches cover up bigger holes, the four smaller round patches are for littler punctures, and the self-vulcanizing fluid bonds tube and patch together on a molecular level, which is code for "really well". Park Tool threw in a small piece of sandpaper, too, so you can rough up the surfaces for a better bond.