This butyl inner tube weigh only 63g, saving up to 45g over generic inner tubes. A pair of them saves 90g of rotating mass. When used as a spare, they are also more compact and reduce the weight of your bag saving even more weight. Advertised as 67g, I weighed 5 of them without caps or nuts, and they weighed 62g, 62g, 63g, 63g and 65g, averaging 63g. Even if you patch them up, they are still significantly lighter than a normal tube. They are less expensive that other light tubes and don’t require the high maintenance of latex tubes but are just as light and have rolling resistance somewhere in between. They frequently go on sale as well. The value is even more impressive when only considering the price on the margin. Performance Bike and Nashbar are the same company, but Performance bike seems to have a better deal when buying bulk, 4 for $21, barely more than normal tubes, but charge more for the long stem versions because they have retail locations and people with deep carbon wheels are willing to pay when they get a flat. Be warned, they have threaded stems for those that dislike that. At $5 and saving 9g per dollar, it represents an exceptional value, moderate cost upgrade. It can be found at Performance Bike or Nashbar.
Price: $5 [Low Cost]
Value: 9.0g/$ ($0.11/g) [Exceptional Value]