Accurate, and simple to use. Bright display. One button control. Solid construction. Great price, I shopped around. Delivery was super fast.
Wait 30 seconds to a few minutes, or leave on longer and you'll get an idea of the range of both your blood O2 as well as pulse. Pulse of course can be checked manually. The O2 range is within what I have seen in my visits to a doctor.
Good instructions and quality built. Quite a number of features. Works well.