Voltcraft-BL-30-AN-Anemometer-Voltcraft-BL-30-AN-P-The-Voltcraft-BL-30-AN-Anemometer-is-a-handy-impeller-meter-with-a-low-loss-magnetic-collector-for-measuring-the-speed-of-wind-&-gas-flow-rate-The-speed-can-be-displayed-in-five-different-units-m-s-ft-min-km-h-mile-h-&-knots-on-the-display-Moreover-the-average-speed-or-maximum-speed-of-each-measuring-process-can-be-determined-&-displayed-on-an-illuminated-display-The-BL-30-is-powered-by-a-9V-battery-P-Voltcraft-BL-30-AN-Anem