I ended up ordering two of the scales because one did not come with the calibration weight. The first scale was not ordered through Amazon as I remember. It's been awhile. The second scale did come with a weight and calibrated perfectly but using the weight from the second ordered scale, the first would not calibrate, and still sits gathering dust. For the price of shiping and the physical hassle of returning it I haven't bothered with it. My fault not the fault of the manufacture. I'm just lazy. The second scale lived up to all my expectations and is used all the time and is very accurate on all the modes. The manufacture has scales that weigh larger items such as gem rough that weigh more than the 350 grams capacity and I won't hesitate to order that model from Amazon or from the same manufacture when I purchase. I've dropped it in the field many times and so far it has taken the beating and kept on ticking. A good buy at the price and is a good value.