Brent Williams of SpeakWisdom shares his thoughts on the Foc.us v2 device along with his recommendations for electrodes.
The V2 Brain Stimulation Device
First, you will need a foc.us V2 stimulator device. They currently sell for about $199 and with current firmware are far beyond any of their competition in terms of versatility, capability, portability, etc. I won’t take time here to list all of the MANY things the V2 can do, but suffice it to say that manufacturers of “professional grade” tDCS, tACS, etc. equipment are probably nervous about where foc.us is driving prices and capabilities! In my opinion, the V2 is THE brain stimulation device to buy at its price point.
Source: Solid Advice on Selecting foc.us tDCS and Accessories