Ceiling PM2.5 sensor, is a based on ZigBee / SmartRoom HA protocol detect airborne dust concentration sensor using optical methods. This product is able to monitor dust in the air, monitoring air quality, and can distinguish between different concentrations of dust particles. This product is widely used, in addition to the common smart home system can also be used in intelligent buildings, municipal works, wisdom farming, factories, and other intelligent systems. Features: 1, supports ZigBee / SmartRoom HA protocol; 2, ZigBee / SmartRoom Device Type: repeater; 3, reliable, stable, accurate data; 4, the minimum detectable particle diameter of 0.5μm;