The FMS18 Fluorescence Dissolved Oxygen Sensors is a SMART optical dissolved oxygen (DO) sensor for use in water and wastewater applications. The sensor Combines high reliability with low maintenance and comes in a standard 12 x 120 mm design. Design features include: • - No Electrolyte Requirement • - No Flow Requirement • - No Oxygen Consumption • - Plug-and-Play with SMART Calibration • - Bubble Deflecting 45° Sensing Surface • - PG13.5 threaded sensor cap • - Retains Calibration History • - Retains User Metadata for Tracking