Ranges:CO2: 0 to 2000; Temperature: 14 to 140°F (-10 to 60°C); Relative Humidity: 0.0 to 99.9% RH.Accuracy:CO2: ±30 ppm ±5% of reading; Temperature: ±0.9°F (±0.6°C); Humidity: ±3% RH (10 to 90%), ±5% (0.0 to 9.9% or 90 to 99.9%).Resolution:CO2: 1 ppm; Temperature: 0.1°F (0.1°C); Humidity: 0.1% RH.Response Time:CO2: < 30 s.; Temperature: < 2 m.; Humidity: < 10 m.Display:4 digits for temperature/CO2 and 3 digits for humidity.CO2 Sensor:Non-dispersive infrared.Temperature Limits:32 to 122°F (0 to 50°C).Humidity Limits (Non-Condensing):0 to 95% RH.Power Requirements:(4) 1.5 V AA alkaline batteries, included, user replaceable.Warm Up Time:30 s.Weight:6.76 oz (200 g).Agency Approvals:CE.