The Aero crown for INspider is an optional extra and completes the elegant integrated aesthetic of the spider, chainring, and crank. It provides minimal air resistance, reduces drag, and allows you to pedal faster with less effort. The Aero Crown reduces the possibility of entry of dirt and external elements towards the chainring side of the bottom bracket, at a point difficult to access for cleaning. The perfect compliment to complete your new INspider power meter.