Great tool for checking to make sure the filters actually work, which all of them did!! This company is excellent at customer service, product knowledge and recommendations, shipping, timely orders, and professionalism. We ordered several units and filters, everything is working in a hard environment to provide clean bacteria free water. We used the test kits on bottled water and were very surprised when the bottled water was dirtier than the filtered water!!!
Reviewed by: g from Mexico.