Only compact meter for a quick measurement of nitrate ion using ion selective membrane.Flat sensor technology and 60 years of sensor engineering realizes a reliable and direct measurement of a drop of the sample from 0.3mL. Use sampling sheet (sold separately) to measure down to 0.05mL or more.Unique sensor mechanism realizes direct measurement of solid, viscous, powder samples. No need for a beaker to calibrate or measure. Just drop the standards and sample on the flat sensor, saves you time and minimize wasting your precious sample.This lightweight, pocket-sized meter is suitable for research and industrial applications in diverse fields.