Ebest - LED Display 6-in-1 Digital Altimeter, Multifunctional as an Altimeter, Barometer, Compass, Thermometer, Weather Station, Clock and Calendar. Produce size approx:3.74"*1.97"*0.63"(9.5cm*5cm*1.6cm) Altimeter: -2296 feet to 29500 feet, Resolution of 1 meter or 3 feet Barometer: Range: 350-1100 hpa, Resolution of 1 hpa Clock & Calendar: With year, month, date, time. Clock format: 24H or 12H(AM/PM) Power off automatic