Features: 11.Easy to use: Just dip a test strip in water for 2 seconds, take it out and wait 15 seconds, compare the color change of each panel with the color chart on the side of the bottle, and you can get the result. 22. Take Free Chlorine, PH and Total Alkalinity Tests: Don't wait until your eyes are burning, don't test your pool with swimsuit bleach, just dip in test strips 33.Easy and quick to use: Accurate PH test strips can test water quality in swimming pools and hot springs to protect your health. 44. Keep your water healthy and clean: With these test strips, they help your swimming pool, spa, whirlpool to maintain proper water chemistry and keep your pool water in healthy and clean condition at all times. 55. Test objects: Free chlorine, pH, alkalinity. Material: paper Size: 9.3*3.5cm Quantity: 50pcs/bottle Test area: Residual chlorine range: 0~10ppm Detectable pH range: 6.8~8.4 Total hardness range: 0-240ppm Uses: Suitable for water testing in swimming pools or spa pools, can test effective chlorine, pH, total hardness, etc. Package Included: 1 bottle of 3-in-1 water test strips (50 Pcs)