For Sport & competition sailing. Teaches hands on skills. Explore wind navigation science.  Length 11 inches, Width 3.3 inches, & Height 17.5 inches.  2- channel control.  Transmitter controls the sail angle & the water rudder.  Equiped with 2 9-gram servos, 3.7V 150mAh Li-Po battery.  Li-Po battery charger is built into the transmitter.  Comes in three colors - Blue, Red, or Green.