Want to replace your mercury sphygmomanometer but don’t want to compromise on accuracy? The greenlight 300 is a new electronic device that has been developed to provide a reliable and accurate alternative to the mercury sphygmomanometer. The greenlight 300 combines manual blood pressure measurement with the reliability and robustness of electronic pressure detection. It is made with the highest quality components, auto-calibrates every time it is switched on, and, for the first time, displays the clinically important cuff deflation rate.