Check the listing for details. AquaChek 511244A 4-IN-1 Chlorine Swimming Pool and Spa Test Strips- 50 Pack. Condition: New. Listed at 11.95 USD. AquaChek 511244A 4-IN-1 Chlorine Swimming Pool and Spa Test Strips- 50 Pack Ships as (1) 1 bottleTest your pool water for Free Chlorine, Total Alkalinity, Cyanuric Acid (Stabilizer) & pH levels with AquaChek Yellow! AquaChek Test Strips are manufactured by the industry leader: Environmental Test Systems (ETS).Simple, fast, and accurate! Get your result in only 15 seconds.Easy to use! Simply dip the test strip into the water.50 Test Strips per bottle.AquaChek 511244A 4-IN-1 Chlorine Swimming Pool and Spa Test Strips- 50 Pack Ships as (1) 1 bottleTest your pool water for Free Chlorine, Total Alkalinity, Cyanuric Acid (Stabilizer) & pH levels with AquaChek Yellow! AquaChek Test Strips are manufactured by the industry leader: Environmental Test Systems (ETS).Simple, fast, and accurate! Get your result in only 15 seconds.Easy to use! Simply dip the test strip into the water.50 Test Strips per bottle.