Hydroponic Essentials  ESPHTEST Hydroponic Essentials pH Test Kit Essentials ph test kit is good for 150 tests At the rate of 3 tests per week it will last one year Kit covers a ph range of 3-10 measuring in 0.1 increments This product weighs 0.2-pound Measures 4-1/5-inch length by 1-1/3-inch width by 1-1/3-inch height