Description : Portable Hand-held Refractometer Salinity Test Marine Reef Hydrometer Features : Used to measure the salinity and specific gravity of the water. Sturdy and light weighted Aluminium body. Superior quality rubber grip. High quality and accurate testing result. Can be easily calibrated with a mini-screw driver. Automatic temperature compensation (ATC) Easy to use, convenient to carry. Specifications : Size(approx) : 195 x 40mm Measure Range : 0-100 percent (0-10 percent ) Accuracy : 0.001sg(1 percent ) Salinity Proportion : 1.000-1.070sg Package includes : 1 x Refractometer 1 x Pipette 1 x Mini-screw driver 1 x Protective carrying case