Measure Range: 0 ~ 200,000 Lux ( 0.1 ~ 18,581 Fc) switchable | Accuracy: ±4%(0~10,000 Lux); ±10% ±5% rdg (above 10,000 Lux) | Record Interval: 1~60 sec / 1~60 min / 1~24 hrs | Windows Compatibilty: Windows 10, 8, 7, Vista and XP (Do not run in Mac OS) | CE Certified & RoHS Compliant

MEASURING RANGE: 0~9999 ppm or 10.0ppt~100.0ppt or 0.0%~10.0% or 0.950~1.080 (S.G.) based on NaCl with ±%F.S ±1 digit / ±0.5°C Accuracy | DISPLAY: Dual Temperature and Salinity in four measurement units (ppm, ppt, %, S.G) / 30 x 18mm LCD Size | APPLICATION: Salinity measurement in fish pond, tank, aquariums, laboratories, food processing, hydroponics, Aquaculture, and other water monitoring facilities. | FEATURES: Waterproof IP65 / One touch calibration / Auto power off and Non-Sleep mode disable / Multi points calibration | POWER SUPPLY / SENSOR : 4 x LR44 button batteries

It has an AC-powered built-in LED light source that provides long lasting ideal illumination | An instrument specially designed for analyzing and viewing if a gemstone is doubly (anisotropic) or singly (isotropic) refractive | Detecting strain diamonds and other gems and separating synthetic amethyst from genuine | With the conoscope, the user can see the different directions the light is traveling through the stone.