The OndaVia Analysis System with the Choline Analysis Cartridge provides a fast, easy choline measurement. The bench-top instrument consumes single-use, disposable analysis cartridges that provide a fast, easy-to-understand measurement of choline levels in water. Whether used to control amine dosing or as a wastewater monitoring system, an OndaVia Analysis System provides fast, easy-to-understand measurements. In contrast to the alternative of laboratory analysis, an OndaVia system gives you the on-site results needed for an immediate response. Cartridges are provided ten (10) per box. All OndaVia kits require an instrument to read the results.