Oxygen Monitor Measuring Range 0 - 21 Percent Oxygen Concentration Accuracy @ 99.995 Percent Ar +/- 0.01 Percent Display Type LCD Display Size 2-15/32 in x 9/16 in Power Source 9V NiMH Cell Battery Overall Height 4 in Overall Width 9 in Overall Length 11 in Features Automatic Self Calibration Internal Pump Data Logging Capabilities Audiovisual Alarm Rechargable 9V Battery 1 yr. Warranty Illuminated Display Programmable in Multiple Languages