Free Chlorine Electio Guide: Portable Instrumenta Q-CL501 Portable Colorimeter for Free Chlorine, Chlorine Dioxide (5-para) Q-CL501B Free Chlorum & Total Chlorine Combined Chlorum Portable Colorimeter Q-CL501P Chlorum & pH Portable Colorimeter T-6800 Multi parametri Portable Colorimeter T-CP40 Portable Colorimeter pro aqua bibens T-SP80 Pooltest Portable Colorimeter Lab Instrumenta Z-T700 Intelligent Multi parametri Analyzer Z-D700 Multi-parametri Analyser Online Analyzer K600 Water Online Analyzer(K-Y02)