Description‎:‎Designed to measure salt water‎.‎ For home‎,‎ or professional use‎.‎ Measures the specific gravity of water or salinity by determining how the liquid affects the bending of light through a prism‎.‎ Main Features‎:‎● Designed for testing the concentration of salt water and brine● Ideal for aquariums‎,‎ marine monitoring and quality control in research and clinical laboratories● Features automatic temperature compensation ‎(‎ ATC ‎)‎● With soft rubber eye piece for comfortable viewing● Soft silicone handle provides good touching feeling● Uses ambient light only which means battery or power source is not required Special function‎:‎ Salinity Refractometer Package weight‎:‎ 0.300 kg Product size ‎(‎L x W x H‎)‎‎:‎ 19.40 x 4.00 x 2.00 cm / 7.64 x 1.57 x 0.79 inches Package size ‎(‎L x W x H‎)‎‎:‎ 21.50 x 8.50 x 6.50 cm / 8.46 x 3.35 x 2.56 inches Package Contents‎:‎ 1 x Refractometer‎,‎ 1 x Screw Driver‎,‎ 1 x Suction Tube‎,‎ 1 x Wipe Cloth‎,‎ 1 x Carrying Case‎,‎ 1 x English User Manual