CT-6110-POL(pH) Residual Free Chlorine & pH, Temperature, Simultaneous display CT-6110-POL(pH) Residual Free Chlorine & pH, Temperature, Simultaneous display CT-6110-POL(pH) Residual Free Chlorine & pH, Temperature, Simultaneous display CT-6110-POL(pH) Residual Free Chlorine & pH, Temperature, Simultaneous display