The TS-1 is a classic & popular pH/ORP portable meter. It features for easy to use tuning calibration, and it is also designed for light weight to carry along with a meter strap as a standard accessory. The meter can also read mV for ORP measurement to enable your flexibility with just the press of a button. There is a manual temperature input tuning knob for accurate temperature compensation, and it is very pragmatic for field measurement especially in a stable temperature environment. The TS-1 stands out from various economical portable meters with accurate and durable quality that you can surely trust on.