HT 501 CO2 Detector Portable Air Quality Monitor Carbon Dioxide Detector for Home Office Item Type: CO2 Detector Material: ABS Model: HT 501 Power Supply: 1 x 3.7V lithium battery(1200mah) (shipped with built in battery) Recording Mode: Manual measurement Instant Measurement Response Time: 1 second Record Storage: 12700 Carbon Dioxide Measurement Range: 0 to 9999PPM Accuracy: ±70ppm ±3% reading (0 to 5000) Resolution: 1PPM Temperature Measurement Range: -10 to 70℃ (14 to 158°F) Resolution: 0.1℃/°F Temperature Measurement Accuracy: ±1℃ Humidity Measurement Range: 0% RH to 99.9% RH Accuracy: ± 3% (10 to 90%) Resolution: 0.1% Working Conditions: 0 to 50℃, 0 to 85% RH (non condensing) Storage Conditions: -20 to 60℃, 0 to 90% relative humidity (non condensing)