Happyaer Hygrometer 4 Inches 4 PCS/set Thermometer Hygrometer Barometer Watches
Happyaer Hygrometer 4 Inches 4 PCS/set Thermometer Hygrometer Barometer Watches Clock Copper for Shell Marine fo 1.Precision temperature sensing hairspring; Precision wet hairspring; Precision gear transmission structure barometer movement; 1 second precision clock movement; Metal 2.Readings Comparison: The contrast pin on the lens is used to compare readings to see if atmospheric pressure rises or falls over a certain period...