... measuring the content & concentration of elements (K, Na, Li, Ca, Ba). It can be widely applied to agriculture (soil, ... , Ba 5 elements. With K, Na, Li, Ca, Ba five filters, which can detect three kinds of elements, ... with numeric keypad.² Single point calibration & calibration curve can be saved.² RS232 interface, external computer or printer. ... (With Air-compress, PC software, can test K,Na,Li,Ca,Ba)