The Triplett Model PH325 Long Tube pH Pen is an advanced pH measurement tool designed for precision and convenience. This unit is features a distinctive long tube design that allows for easy access to hard-to-reach areas, making it an ideal solution for a variety of applications. The PH325 features a simultaneous display of pH and Temperature angled perfectly for viewing, 1-, 2-, or 3-point calibration, and a Hold function to “freeze” the reading on the display for easy viewing. This unit also has a waterproof rating of (IP65) which increases the usability and functionality of this unit.