You’ve trusted the Sigma area velocity sensor for years. Now, the new Hach AV9000 makes it even more reliable. Features include factory default settings for streamlined set up and optimized battery life. Analyzer diagnostics include: multi-scale Doppler spectrum, diagnostic statistics and loggable quality parameters. It has increased accuracy with speed-of-sound compensation. It also features onsite sensor operation verification prior to leaving the site, and the option is available to log raw level data.