Columbus Pro microplate washer is offered for applications ranging from diagnostic tests to cell based research. The instrment achieves high wash performance by having very low residual volumes (less than 2 μl) and multiple aspiration points for each well. Leak-proof aspiration pump incorporates, which provides static seals to enhance the lifetime of the pump and provide reliability of the whole washer system. In the Columbus Pro, overflow washing replaces tedious sequential aspiration and dispense steps with a single procedure. This guarantees best wash-efficiency without compromising throughput. Fill verification option permanently monitors the wash procedure and automatically detects clogged needles. Another option controls the liquid levels of the wash buffer, rinse and waste bottles.