Features: THE ULTIMATE AT HOME POOL TEST STRIPS for your swimming pool & spa. Tests for 16 parameters: total hardness, total chlorine, bromine, free chlorine, pH, cyanuric acid (stabilizer) & total alkalinity. EXTREMELY EASY TO USE pool water test strips, Instant reliable results with simple and clear instructions. Simply dip and compare with large color chart on bottle. for Ideal range marked on bottle. BONUS FREE MOBILE APP INCLUDED - Record, track and monitor your pool test strip results with ultimate accuracy. Available for Android50 STRIPS MEANS 50 TESTS - Each swimming pool test strip provides accurate and fast results for any water sources including for fresh and salt water pools, spas and hot-tubs. GET SAFE, CLEAN AND CRYSTAL CLEAR WATER, our pool and spa test strips come with a great e-book explaining what your results mean and how you can keep your water in a healthy and clean condition year round. Specifications: Material: Paper Size: 12cm/4.72 inch Package Includes: 1 Set Water Test Strip note: 1.Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you place order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!