The Stingray 2.0 battery-powered, area-velocity flow logger from Greyline Instruments records level, velocity and water temperature readings through open channels, partially full sewer pipes and surcharged pipes. Rated for operation in temperatures from -4 to 140 degrees F, the logger operates up to four years on standard alkaline D-cell batteries. 888/473-9546; www.greyline.com.
