The 3 common sorts of pH meters are pen-type meters, handheld meters, and benchtop meters, all of which provide the same purpose but change in layout and in some cases in capacity. Pen-design and style pH meters are compact and handy but often deficiency the accuracy of benchtop pH meters. https://alkaline-anytime-thermos21098.dm-blog.com/20113894/about-best-alkaline-drops