Grade 4 and up. Using safe, reliable, one-step dip strips sealed in foil packets, this kit fits easily in a shirt pocket, yet contains enough material to test 10 water samples for free and total chlorine, pH, total alkalinity, total hardness, nitrate and nitrite, nitrogen, total copper, and total iron. Results are presented quantitatively as parts per million (ppm). Testing is simple: just dip the end of the test strip in the water sample, swirl for the specified amount of time, and compare the resultant color with the color chart on each foil packet. Plastic water sample vial is included.