... N, P, K, humic acid , organic matter, salinity, and PH in the soil, fertilizerand plant2.With the function of time display ... , variety and so on.5.Big-screen LCD shows, and will guide you how to operate.6.When in the test, it has the ... ) Stability: A(absorbency of illumimation) drift less than 0.003 in three minutes.2) Repetitiveness: A(absorbency of illumimation) less than ...