Dwyer A-SAH-24S is a Smart Air Hood® Balancing Instrument designed for air flow measurement. It operates on a 3.6V NCR18650B MH12210 lithium-ion battery (included) or (4) 1.5V AA alkaline batteries (not included). With a quick 1-second response time and 1 CFM resolution, it can accurately measure air flow ranging from 40 to 2000 CFM (68 to 3398 m3/h) for supply and 80 to 2000 CFM (136 to 3398 m3/h) for exhaust. It uses Wi-Fi direct low energy wireless technology and supports the SMART Air Hood® application software, available only with the factory supplied test instrument. Made of polypropylene material, it ensures durability. The accuracy is >40 CFM, with a ±3% reading ±7 CFM (11.9 m3/hr) (3.3 l/s) accuracy. Operating in CFM, m3/h, and l/s units, it is an efficient and reliable tool for air flow measurement in air systems.