TruTest Strips used with the Aqua Chek Trutest Digital Reader. These simple-to-use strips are specifically designed for pool and spa owners to test the chemical content of their water. Simply dip the strip into your water and place in your handy Aqua Chek Trutest Digital Reader (sold separately). The strips accurately reads chlorine, bromine, pH, and total alkalinity. 50 count. Easy-to-use water test strips for pools and spas Test twice a week to keep your pool at its best Test your spa before every use 50-pack Trutest test strips For use with Trutest digital reader (sold separately) Color: Blue.