Perfect for testing chlorine / bleach sanitizers and avoiding hefty board of health fines! Food service and restautaunt industry leading rapid one second chemical sani test Tests in a range of 10-200 ppm (10, 50, 100 and 200 ppm markings) These are NOT for pool OR tap water tests. They ARE designed specifically for restaurants testing their chlorine sanitizers in 3 part sinks This strip is ideal for commercial dishwashing and three part sinks, but not all applications. It absolutely will not work for testing undiluted Sodium Hypoclorite (chlorine/bleach). It will ONLY give a reading up to 200 ppm. Each vial has an expiry date and lot number printed on them for compliance purposes. These are NOT for testing pools, hot tubs, OR tap water.