... Refractometer, Abbe Refractometer, PH/DDS/TDS Meter, etc.Application:This instrument is used for analyzing & measuring the content & concentration of elements ... ;Na: 0.01ppm;Drift≤ 3% (after 30 minutes when the instrument stability)Sample Rate4 ~ 6ml/minLinearityBetter than the best results of ... -AP1500 Flame Photometer/Spectrophotometer (With Air-compress, PC software, can test K,Na,Li,Ca,Ba)