I think it is .5A, 1A, 2A; its the load so the load selection is 500ma, 1000ma, and 2000ma. Putting the load on the battery lets you measure it while it is trying to work. You are looking to see if the battery can hold its voltage while it is working, so when you use it, you should see no less than 4.8v for a 4 cell or 6.0v for a 5 cell nicad or nimh because at that point it is at the bottom of the charge. Anything above is good.