ACCUSENSING is a professional environmental sensor manufacturer with the ability of research and development. By developing fast and accurate monitoring devices for environment, we expect that increasing environmental problems will be substantially solved by significantly reducing sample analysis time from weeks to minutes. For detecting heavy metals in water or liquid samples, our product MAS only requires four easy steps, which presents a digital reading within 3 mins. MAS features pretreatment-free, calibration-free and user-friendly for non-technical persons and has high correlation(r2>0.95) with laboratory instrument. MAS has obtained Taiwan invention patent (certificate no. I658267).