The Aerocet 831 is a completely portable, full–featured, battery operated, handheld mass monitor. This device simultaneously provides five critical mass ranges (PM1, PM2.5, PM4, PM10 & TSP) in one minute from start up. Survey the environment with the easy to use, extremely portable, size selective Aerocet 831. Weighing only 28 ounces, this compact instrument is the perfect tool for a wide range of assessment applications.