Chlorine Testing Pen 4-in-1 Water Chlorine Content Measuring Pen Swimming Pool Chlorine Measuring Instrument Water Chlorine ORP H2 Temperature Tester

Features:
Clear LCD display screen, large screen display, clear numerical values, easy to read.
Using three button batteries, and battery replacement is convenient.
High sensitivity electrode probe, high accuracy in measuring water quality, automatic temperature compensation, reducing errors.
There are four different modes for the test pen, and pressing the MODE/CAL button can switch between different modes.
Mode memory function, default mode for each startup is the lastmode used before shutdown.