Casio Pro Trek PRG-340-3ER

About the Watch

Built as a digital outdoor tool, this Pro Trek model combines watch functions and measurement data in a clearly instrument-focused display. The green design is accented with yellow and orange markers, while the duplex LCD divides graphic and numerical information between two layers for a larger and more readable direction display. Casio targets the series at nature enthusiasts, highlighting climbing, navigation, and longer treks as central use cases.

Material & Fit

The case measures 54.7 × 51.7 mm and is 15.1 mm thick; the total weight is 54 grams. The case, case back, and the soft urethane strap use bio-based resin from renewable raw materials, with Casio specifically mentioning castor oil plants and corn. Mineral glass covers the display. The movable lug construction allows the case and strap to lie flat on a paper map, and the specified wrist interval is 145–215 mm.

Highlights

• The Triple Sensor includes a digital compass, barometer, altimeter, and thermometer; the altitude range extends from −700 to 10,000 meters.
• Tough Solar charges the watch with light, providing approximately seven months of operation without new exposure, or 27 months in darkness with power-saving mode activated.
• Water resistance is 10 ATM, a level suitable for swimming.
• The construction is specified for temperatures down to −10 °C, and the stated precision is ±15 seconds per month.

Good to Know

• What is the rotating bezel used for? It can mark a compass direction as a simple orientation reference.
• How are measurement modes accessed? Separate direct buttons open the sensors with one press, and the large buttons have a non-slip surface for use with gloves.
• What time functions are included? World time covers 31 time zones, and the watch displays sunrise and sunset for the selected date, as well as a stopwatch, 24-hour timer, and five daily alarms.
• How is the display illuminated? A white, full-auto LED backlight with afterglow is used in the dark.