16 IN 1 UPGRADE: Our Pool Test Strips upgrade pack 16-way test strips for PH, Total Chlorine, Free Chlorine, Total Alkalinity, Cyanuric Acid, and Total Hardness. QUICK AND ACCURATE:Simply dip one strip in water for 2 seconds, then remove it.Hold the strip horizontally for 30 seconds.Compare with the color chart and read within 30 seconds. RESULTS HIGH ACCURACY: 100 count PH test strips are made of high quality imported filter paper. Each spa test strip with 16 color indicators, high precision and reliable instant reading. CONVENIENT TO CARRY: Portable bottle, it is very convenient to take it anywhere. 1 bottle contains 100 Swimming Pool Test Strips. WIDELY APPLICATIONS: These strips are widely used for aquarium, spas, baths, hot tubs and other water chemistry testing. Research shows that you should test your pool and spa at least twice a week, so you can monitor the quality of your water at regular intervals! Precision: 96% Shelf life: 1 year Material: PET Trial time: 30s Advantages: Test strips and packaging can be customized according to customer needs Scope of application: suitable for drinking water, aquarium, swimming pool and spa, industrial water, pond, hot spring water. Package list: 100 pieces/box