UltrAspire Extra Battery Battery size:18650 We sculpted our full-length Air

We sculpted our full-length Air Zoom unit to deliver a propulsive feel and Nike's highest energy return from heel to toe-off

The upper is constructed from a Kevlar-infused woven mesh

This setup creates a smooth

featherlight races

UltrAspire Extra Battery Battery size:18650 We sculpted our full-length AirThe UltrAspire 21700 Battery is pairs with the Lumen 800 Solstice Waist Light to ensure you have power to run through the night. *This battery pairs ONLY with the Lumen 800 Solstice. For any other 3D Waist Light, please see our UltrAspire 18650 Battery. The UltrAspire 18650 Battery has 3400 MaH and is programmed for low amperage output to ensure your Lumen has the optimal power source for the best performance on the road or trail.