I wanted to be able to test the pH of my urine and saliva at home to help monitor my osteoporosis. I needed pH strips that covered sub-levels and that could be read with some degree of accuracy. These strips have two squares on each one that are different colours making it easy to compare them with the chart supplied in the handy, discreet pack. I am very pleased with them but I have found it hard to get the top off their container resulting in them falling out all over the floor on one occasion.