This is an optional Blade Sport Propeller Set. These Sport Propellers will allow for inverted flight while the 3D Propellers will allow for more advanced maneuvers while inverted. Like all performance upgrades there is a compromise to be made. Using the 3D Propellers with more advanced maneuvers will cause the battery to drain faster yielding shorter flying times with the stock battery.
This product was added to our catalog on August 19, 2014