Perfect fit for ultra-micro helicopters like the E-Flite Blade mCX, mCX S300, mSR, 4-Site and ParkZone Vapor, Ember, J-3 Cub, Sukhoi Su-26m, P-51D Mustang, Cessna and Hobby Lobby eRC Mustang, Spitfire.

Get longer flight times, more power, and more cycles.

Note: Always grab the battery by the black plastic base.

Includes:

4 - Lipo 150mah 1S 3.7V batter...

Field Link allows you to modify the most commonly used settings in your Castle controller all at the touch of a single button.  Simply connect the Field Link to the throttle lead of the controller to power up. Click the button to scroll through and change the indicated settings.  That easy!

This programming card also works as a standard Castle Link that gives you acc...