The Pentype DO meter is a portable device designed to accurately measure the dissolved oxygen (DO) levels in liquid, particularly water. This device offers a convenient and portable solution for outdoor testing purposes, allowing easy transport to various locations. It provides precise measurements of dissolved oxygen and temperature, ensuring reliable data collection. A standout feature of this device is its one-key 100% DO calibration, eliminating the need for any chemicals during the calibration process, thus simplifying the setup and reducing maintenance requirements. Maintaining this equipment is hassle-free due to its high sensitivity membrane set. The manual salinity and barometric pressure compensation further enhance its accuracy and adaptability to different environments. Additionally, the device comes equipped with an easy-to-replace thin membrane kit and quick-to-refill electrolyte, streamlining maintenance tasks and reducing downtime. It is an essential tool in numerous fields, including environmental monitoring: