High efficiency 20 uL mixer using micro reactor technology to thoroughly blend solvents in a small volume. This mixer is recommended for UHPLC systems requiring minimal system dispersion without an optical detector, operating at analytical flow rates (~1 mL/min) and LCMS flow rates with solvents from pH 1-14. This mixer includes a Mixer Recognition Device which will log the volume of the mixer in the system configuration when used with the CTO-40S/C oven and LabSolutions.