Review on AR1890P2 Manometer Differential ±13 79KPa with Perfect Prime by Justin Early

This product comes with a quick start guide only which has absolutely no information about this specific product. The quick start guide has a section to download the "complete guide". I scanned the QR code and found myself in a section with perfect prime number tutorials that had no information about the digital manometer. It listed many of their other products so I sorted the list just to be sure. I don't know how a company can expect you to use a product when there is absolutely no downloadable manual for it and it isn't included.