Dip Test Strips are a quick and easy way to check chemical levels in your above ground pool or hot tub. Brand New and High Quality Type: Swimming Pool SPA Test Strip Quantity: 50 / bottle Size: As the picture shows Package Include:1*Bottle Test Strip (50PCS) Features: 1.Quickly measure pH, Chlorine and Alkalinity. 2.Identify any necessary chemical adjustments. 3.Reliable and accurate readings. 4.Easy to follow instructions. Measures: 1.pH: Measure the pH levels of your water to so you can ensure the water is safe and comfortable to use. pH levels should be 7.2 7.6 2.Chlorine: Ensure you have the correct amount of chlorine in your pool or hot tub to help prevent bacteria and harmful organisms. Chlorine levels should be 1-3 mg/litre (ppm) for pools and 3-5 mg/Litre (ppm) for hot tubs 3.Total Alkalinity: Measure the total alkalinity levels to help prevent your water becoming corrosive. Levels should measure 80 100 ppm or 100 120 ppm