YSI 600XL Multiparameter Water Quality Sonde Supply Sales the Defender 500 series incorporates

the Defender 500 series incorporates features to make it immune to flow source pulsation without the need for in-line dampers

The fault light indicator is activated when the pump attempts to operate outside  ±5% of the required flow rate

The Widest Flow Range of Any Personal Air Sampling Pump

dual-input HQ2000 series

YSI 600XL Multiparameter Water Quality Sonde Supply Sales the Defender 500 series incorporatesBoth the YSI 600XL (sampling) and the YSI 600 XLM (logging) are economical solutions in small packages for surface water and groundwater applications. Both easily fit into 2 inch wells and measure a range of fundamental parameters, including oxygen with the YSI Rapid Pulse stirring independent dissolved oxygen sensor and level, using a highly accurate vented sensor.