This is the Microheli CNC Main Gear for the E-Flite Blade CP and Blade CP Pro helicopters using the Micro Heli CNC Main Gear and Hub. This gear is stronger and more durable than the stock gear. This gear is 100% CNC-machined for the smoothest operating performance possible. This will not be a direct replacement gear for the stock E-Flite gear, only on the Micro Heli hub.