The Apera Instruments AI421 PH400S Portable pH Meter Kit is a reliable and highly accurate testing instrument designed for professional use in laboratories, environmental monitoring, agriculture, water treatment, and industrial settings. Featuring a measurement range of -2.00 to 19.99 pH and a resolution of 0.01 pH, it delivers precise readings crucial for quality control and research. The unit is built with durable materials and a robust housing that withstands routine handling in demanding environments. Its compact dimensions—1.3 inches in height, 3.4 inches in width, and 7 inches in length—make it easily portable without compromising on functionality. A standout feature of this pH meter is its GLP (Good Laboratory Practice) data management capability, which stores up to 500 groups of measurement data with time and date stamps. This ensures traceability and simplifies record-keeping for compliance purposes. The USB data output allows convenient transfer of logged data to a computer for further analysis or printing. Such data handling is especially valuable for professionals who need to maintain accurate logs in quality assurance, field surveys, or academic experiments. The kit includes a high-quality pH electrode, calibration solutions, and a carrying case, providing everything needed for accurate testing right out of the box. The electrode’s design ensures quick response and stable readings across a wide pH range. Calibration is straightforward, and the meter automatically recognizes buffer solutions, reducing user error. The backlit display and intuitive button layout enhance ease of use, even in low-light conditions.

The Apera Instruments PH400S kit offers a balanced combination of precision, durability, and practical features at a competitive price point. It suits a broad range of users—from scientists and technicians to hobbyists—who require dependable pH measurement with efficient data management. The thoughtful construction and reliable performance make it a solid investment for consistent, long-term use.