Hydroid QT-10 Quaternary Test Paper provides a simple, reliable, and economical means to measure the concentration of Quaternary Sanitizers, including n-alkyldimethylbenzyl and/or n-alkyl dimethyl ethyl benzyl ammonium chloride, and Rocall II. With color matches at 0-100-200-300-400ppm (parts per million), the test paper measures concentrations between 0-400ppm, detecting exhaustion of solutions that should be replaced as well as helping to avoid using excessive amounts of sanitizing agents.