Brand New Portable CO Detector with Alarm. Advanced CO Detection: The highly sensitive device can detect 0-999ppm carbon monoxide concentrations. Ensuring accurate & early detection. LCD Display with Real-time Data: The built-in LCD display is easy to read. Instant Alarm & Visual Indication: In the event of elevated carbon monoxide levels the alarm will sound & LCD display flashes with warning. And will alert for low battery as well. Dimensions: 6.7 x 1.2 x 2.6 inches