1.Upgrade 6 inches (about 6 cm) 1 liter: test PH, total chlorine, no chlorine, total alkalinity, acid purification, full hardness, etc., more powerful than 5 or 4 pool test panels and liquid test tools 2. 17S test: There are 2 test strips for underwater soaking pools, keep about 15 in the air, and then match the color of the strip to the color on the back of the bottle, which takes about 17 seconds. Pool test strips are easy to use and even suitable for beginners. 3.Environmental protection: The water quality of the pool should be tested weekly. of test strips includes 50 pool test strips and seals, 5 moisture-proof packages to long-term storage. 4. Health: Test strips are used for swimming pool, spa, hot tub water testing, and you can that the right amount of chemicals are in the pool to avoid health problems and equipment damage. 5.Test twice at the pool twice a week for best results.A good way to easily understand your water quality in the key. Type: 6-In-1 Swimming Pool Test Display Type: Digital Test: TC, , PH, ALK, CYA, Test Range: Total chlorine test range: 0 ~ 10ppm Free chlorine test range: 0 ~ 10ppm PH test range: 6.8 ~ 8.4 Total alkalinity test range: 0 ~ 240ppm Total hardness test range: 0 ~ 1000 Cyanuric acid test range: 0 ~ 240 Colour:As shown Material:PET Size:9.7*3.5cm Package Contents: 50*Swimming pool test strip Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.