... checked at any time.Can print testing data, sample No, testing item, sample content, variety and so onBig LCD display, easy ... : above technical parameters all exceed national standards)2. PH technical parameters:Testing range: 1-14Error: ±0.13. Salinity technical parameters ... 18V, 5W (With tester) Function:Test N,P,K, PH, organic matter, soil PH, soil salinity, with storage and printing function