Single point is almost always done at the 7.0 position. Single point is fine as long as the area you are testing is within the neutral zone of 5.5 to 8.5. However, for accuracy in most applications, you need to have two point calibration. That is why most Milwaukee Instruments come with a 2 point calibration procedure, and most of our units are provided with both 7.01 and 4.01 calibration solution.
