Adjustable Power Source - Hot Wheels

This is a case for a variable power supply. I use it to power the Hot Wheels Booster Motors. I soldered wires to the positive and negative battery terminals in the booster to bypass the batteries. Set the power source to 5v and control it with the board below. Allows you to overclock the motor or slow it down.

http://www.amazon.com/DROK-Numerical-Switching-Adjustable-Stabilizers/dp/B00BYTEHQO?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00

http://www.amazon.com/ZOZO-Universal-S