Feature:Convenient to use, simple to operate, solid quality.Could test soil pH soil fertility.It's lightweight and portable design, convenient for indoor and outdoor use.Battery is no need; easy to operate.Ideal soil test tool kit for flowers, vegetable, gardens, home potted plants,lawn and farm. Using Method:1. Measuring soil pH, as far as possible to probe deeply into the earth and probe the upper portion for about 1 cm.2. On the table is 2.5-9 numerical, numerical 7 basic is neutral, the smaller the number shows that the greater the acidity, please adjust soil pH value according to plant varieties.4. Please pay attention that insert electrodes without touching the stone, not too hard, otherwise easy to damage the electrode, clean electrode after use.Specification:Material:Plastic Accuracy: About 0.25 pH(20)0.2 pH (Suitable for farm or education experiments)Working Temperature: About 0 - 50C(32-122F)Size: 11 x 6 x 3 cm / 4.33 x 2.36 x 1.18 inch (appr.)Probe Length: 22cm / 8.66 inch (appr.) Soil pH for optimal growth of major crops:Crop namepHCrop namepHCrop namepHRice6.0-7.0Peanut5.0-6.0Chestnut5.0-6.0Wheat6.0-7.0obacco5.0-6.0Watermelon6.0-7.0Corn6.0-7.0Tea5.0-5.5Cabbage6.0-7.0Soybean6.0-7.0Potato4.8-5.4Tomato6.0-7.0Sugarcane6.0-8.0Orange, mandarin5.0-7.0Pumpkin6.0-8.0Sweet potato6.0-6.0Lychee6.0-7.0Cucumber6.0-8.0Package Included: 1 x Soil pH Level TesterNote:Customers are advised to strictly follow the instructions for use, and there are instructions on the back of the package..