Features: Small size, light weight, easy to carry and operate. With a low power consumption & high precision.Stablized sensor. Continuously monitor the concentration of CO gas in the surrounding environment. Sound and light warning works when CO gas concentration reaches the level of the warning. Widely used in petroleum, chemical, coal, metallurgy, paper,municipal, telecommunications, food, textile and other industries. Package Includes: 1x Carbon Monoxide Meter Specifications: Material: Plastic Package size: approx 18.5x8.5x5.2cm/7.3x3.3x2in Measurement unit: PPM Range: 0-1000ppm Resolution: 1ppm Alarm: sound and light alarm Alarm point: low: 35ppm; Medium: 70ppm; High: 200ppm Operating temperature: 0-50C Operating humidity: 15%-90% RH (non-condensing) Power supply: 3 AAA 1.5V batteries (not included) note: Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item.