This is an expensive little wireless handpad. It works beautifully though. NO set up, plug it in and go. The power for the receiver is from the controller. There is a short wire to connect the little box on the right to the servo controller. The handpad itself is powered by a 9 volt battery. A neck string is included. There is also a red flashlight built into the front of the handpad. 
If you click on the picture, you can see there are small lights for the different motor speed levels. The computer also has a voice function that comes on when you change speeds.