920-5497, Testo, Testo 315-4 Handheld Gas Detector for Carbon Monoxide Detection, Audible Alarm, Brand Testo, Gases Detected Carbon Monoxide, Accuracy ±0.5 (Temperature) °C, ±2.5 (Humidity) %RH, ±5 (CO) ppm Testo 315-4 Handheld Gas Detector for Carbon Monoxide Detection, Audible Alarm