| specifications | R818 |
| Operating Humidity | 0~99% relative humidity(non-condening) |
| Measurement range | 0 to 1000PPM |
| Measurement Resolution | 1PPM |
| Accuracy | 5% or ±10PPM |
| Warm up period | <2 seconds |
| Operating Temperature | 0℃to5℃ |
| Storage Temperature | -30℃to60℃ |
| General Characteristics | |
| Power | 9V Battery |
| Product Weight | 162.2g |
| Product Size | 159mmx59mmx41mm |
Source: https://www.meterstesters.com/products/carbon-monoxide-detectors/carbon-monoxide-meter-r81.html