Rugged and reliable, the YSI Pro20 provides everything you need in a handheld dissolved oxygen instrument. User-replaceable sensors and cables (choose polarographic or galvanic for the field or a self-stirring BOD probe for the lab), 50 data set memory, and the convenient One Touch Cal feature allows for easy DO calibrations within 3 seconds with the press of a button.

Mil-spec (military spec) connectors, IP-67 waterproof and rubber over molded case, and 1-meter drop tests ensure the instrument remains in your hands to provide years of sampling even in the harshest field conditions. Fast response times allow you to complete your sampling routine quickly, saving time and money.