Model Number: ETP303 Brand Name: TLead Key Specifications/Special Features: Give accurate results of the pH and fertility of the soilNo batteries requiredpH portion of the tester utilizes the chemical reaction known as oxidation-reduction to measure pH within the range of 1-9Fertility portion of the tester measures the soil's nitrogen, phosphorous and potash (NPK) content, in combinationFertility is within the range of too little, ideal and too much, with probe 85mm