got it in the mail and plugged it in and oll that shoed up on the digital read out was a lot of dashes. I could not get the numbers to  show so I returned it for a replacement. The new one did the same thing untill I turned the upper container to click in lock posision. I wish the instructions would have told me that the dashes turn to numbers after you click it into lock possision. That is my only complaint. It is a great tool. A top quality product.