Physical Specifications

• The Casio Protrek PRG-40, released in the year 2000, is 21.18 inches wide, 2.24 inches high and 7.05 inches thick. The watch contains a resin body and band with a stainless-steel backing that shields its internal components and battery. The The Casio Protrek PRG-40 contains a mineral crystal covering over its LCD display. The watch's bezel turns manually and is part of its crystal covering.
  
  

Compass Specifications

• The watch's digital compass measures and displays navigational direction as one of 16 points, and includes a bi-directional calibration control. The Casio Protrek PRG-40's compass measuring range is 0 to 359 degrees. When it encounters an abnormal magnetic field, the watch will alarm you of the incorrect field and automatically recalibrate the compass once you are past the it. The compass also includes a northerly calibration function.
  
  

Temperature Measurements

• The Casio Protrek PRG-40's thermometer function displays temperature values in both Fahrenheit and Celsius in a format of "0.1°C" or "0.2°F." The watch's temperature display range is -10 to 60 degrees Celsius (14 to 140 degrees Fahrenheit ).
  
  

Barometer Measurements

• The watch's barometer function measures atmospheric pressure and presents it in a graph on the watch's LCD display. The graph is known as a tendency graph and each barometer display unit is equivalent to 1 hectoPascals (hPa/mb) or 0.05 inches of mercury (inHg). The watch is capable of measuring and displaying a barometer range of 260 hPa/mb to 1,100 hPa/mb or 7.65 inHg to 32.45 inHg.
  
  

Altimeter Measurements

• The Casio Protrek PRG-40 also measures the altitude of a specific object above a fixed point, also known as an altimeter measurement. The watch's altitude measuring unit is in 20 feet increments and the altimeter measuring range is -2,300 to 32,800 feet. The Casio Protrek PRG-40 is capable of storing up to 50 sets of data and calculations including altitude value, month, date and time of reading. When you reach specific altitude, the Casio Protrek PRG-40 alerts you with an audible alarm.
  
  

Battery Specifications

• Four SR927W batteries, available at electronics/computer supply stores, retail superstores, watch repair shops and online battery resellers, power the watch. The batteries need replacing approximately every 18 months.
  
  

Additional Specifications

• The Casio Protrek PRG-40 also includes five different audible alarms programmable via the watch's "Mode" and "Adjust" buttons. The watch's stopwatch is programmable to 1,100th of a second and is also adjustable via the "Mode" and "Adjust" buttons.