MULTIPARAMETER WATER QUALITY METER HQ40d Portable pH, Conductivity, Optical Dissolved Oxygen (DO), ORP, and ISE Multi-Parameter Meter Designed for water quality experts, the Hach HQ40d portable meter is an advanced meter that takes the guesswork out of measurements. HQd meters connect with smart probes that automatically recognize the testing parameter, calibration history, and method settings to minimize errors and setup time. The durable portable meter and optional rugged probes are designed to withstand years of rugged portable and field use. HQd meters feature a simple user interface that does not require manuals or training to operate. This package features the rugged optical dissolved oxygen (LDO) probe for year of worry-free use around the plant or in the field. Portable meter measures critical water quality parameters - without the need for multiple instruments Intuitive user interface for simple operation and accurate results Trust your measurements - IntelliCAL™ smart probes store all calibrations in the probe Designed for demanding conditions Convenient kit includes everything you need to start testing