1、HIGH ACCURACY RESIDUAL CHLORINE TESTING PEN: Our residual chlorine test pen is equipped with automatic value locking, automatic temperature compensation, and it pioneers the electrode method for residual chlorine testing. 2、AUTOMATIC TEMPERATURE COMPENSATION: The residual chlorine test pen automatically compensates for temperature variations to ensure accurate and reliable test results. 3、AUTOMATIC VALUE LOCKING: With the automatic value locking function, the residual chlorine testing pen locks in the reading, allowing for easy and convenient recording and analysis of test results. 4、MULTI LINE BACKLIT DISPLAY: The chlorine tester features a backlit screen with multiple lines, providing clear and easy to read measurements, even in low light conditions. 5、WIDE APPLICATION: Our residual chlorine monitor is suitable for various scenarios, including large swimming pools, sports stadiums, private pools, outdoor pools, hot springs, and spas. Its versatility makes it an ideal choice for water quality monitoring in different environments. Item Type: Chlorine Test Pen Material: ABS Measuring Range: 0.00 to 10.00mg/L Operating Temperature Range: 0 to 60℃/32 to 140℉ Temperature Compensation: ATC automatic, MTC manual Automatic Shutdown: 10 minutes Temperature Measurement Range: 0 to 100℃/32 to 212℉ Protection Level: IP67 Automatic Backlit: 1 minute Battery: AAA battery x 1 (shipped without battery) 1 x Chlorine Test Pen