Waterproof PTTestr 35

Easy-to-navigate, four-button scroll menu

With three different choices, you can get the one Meter you need instead of having to buy multiple single-parameter units. That has a lot of benefits: you only need to remember to bring one Meter along with you, you only need to replace one set of batteries and, best of all, you only have to carry one Meter in the field, which leaves room in your pack for a sandwich. All of these Meters have automatic temperature compensation and one-point, push-button calibration so you get accurate results. And they float, so if you fumble your Meter and it takes a swim, it'll bob to the surface for easy retrieval. Sensors are easily replaced by hand. Each includes four 1.5V batteries and displays the measured value and temperature.