I use two chargers and one power source. I have the 206 charger that goes to 20 amps, and the HK 250 that does 10 amps. I also use a converted Hewlett Packard 750 computer power supply that is rated at 62.5 amps. It takes 10 minutes to convert one to rc. All three items are very small. The first time I used this system I was surprised at how fast my batteries charged. I used to buy 2 batteries for each car because the charger before was so slow, Peak 620. Now I only get one battery per car. These things charge fast.