Just got this charger along with my provari the other day and had a question about a feature on the charger. I have attached a pic so you can see what im talking about. The switch next to the USB port, with the 3 settings (1A 0.5A 0) What is it for and what should I have it set at? I have an 18490 battery btw but I dont know if that has anything to do with where the switch needs to be set at

