Couldn't get it to turn on. Finally got it on with the included batteries.
Maybe bad contact with metal on battery door. Hinge is loose and I just kept trying. But I can't vouch for its accuracy. My upper arm unit is too hard to deal with which is the reason I bought this. And I'm not going to the doctor soon. When I do get a fair comparison I will write another review. I gave 2 stars because it seems like a well made unit and for the price I'm willing to give it the benefit of the doubt
Rating: 2 stars