Hydrion QT-2000 Quaternary Test Kits provide a simple, reliable, and economical means to measure the concentration of 2-chain and 4-chain Quaternary Sanitizers. With color matches at 0-200-400-600-1000-1500-2000 ppm (parts per million), the test paper measures concentrations between 0-2000 ppm, detecting exhaustion of solutions that should be replaced as well as helping to avoid using excessive amounts of sanitizing agents.