PCE-0100 is a handheld refractometer used to determine the salt content or % salinity ppt and salinity SG (specific gravity) of salt water, sea water and other solutions containing a concentration of salt. This portable pocket salinity refractometer has a double scale to allow the user to view both measurement parameters at once. The ultra-smooth focusing eyepiece provides high-quality optics, presenting an easy-to-read scale on a semi-transparent blue and fully transparent clear background. Ambient room lighting offers ample illumination to clearly read the results.