AeroDefender wheel fairings

How much are you willing to compromise on looks for gain in speed?
The makers of the AeroDefender wheel covers claim significant gain in speed, of up to 20%, by covering the upper section of the wheel and reducing drag where it matters. Their website is full of technical details, albeit short on wind tunnel testing. Please head over to their site (link below), if you like to learn more.

The fairings fit on road bikes with conventional diamond frame geometries (75-100 mm wide @ 30 cm from axle). Versions exists for both rim and disc brake bikes. Since you might want to try if and how they fit, Nullwinds offer a 30 days return & refund.
You can get carbon fibre AeroDefenders for USD 399, and a budget fiberglass version for USD 299.
No information is available on weight.

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