These monitor/controllers are perfect for ultrapure water applications. Precise dual-thermistor circuit for temperature compensation matches Pure water temperature coefficients-ensures accurate measurements over the entire range. Order resistivity cells separately. In-line stainless steel cells can withstand temperatures to 212°f (100°c) and pressures to 100 psi! NEMA 4x (IP65) ABS plastic enclosure feature a heavy-duty 10 amp relay NEMA 4x (IP65) ABS Enclosures.