0-10% Sea Salinity Refractometer Meter Ocean Water Salt Concentration Aquarium Handheld Mariculture Breeding Gravimeter Analyzer Features: 2 in 1 design to measure the Specific gravity (sg) of the salt solution and concentration of Nacl Easy to use, sturdy design, compact in size and light in weight, convenient to keep up and carry arround. With Built-in ATC (Automatic Temperature Compensation) from 10~30 degree Celsius. Soft Rubber eyepiece for comfortable viewing Equipped with scale measurement which provides direct reading Accurate testing results guaranteed Durable and bulit to last long Adjustable manual focusing Use ambient light only which means battery or power source is not required We provide Manual in English, French, German, Spanish, Italian, Japanese, Ruian . How to Use: 1. Align the Cover Plate with light, adjust the Focus Adjustment until you see the scale clearly. 2. Calibration: Accurate Measurement depends on careful calibration. Please make sure the ambient temperature is about 68 F, distilled water can be used to calibrate. Open the Cover plate. place 2-3 drops of the distilled water on the prism, then close the cover plate and make sure the water spread aro the prism without any air bubbles or dry spots. wait for about 30 seconds to let the reading to stabilize. Look into eyepiece and turn the calibration screw with the screw driver until the reading is "0" 3. Clean the prism with soft cloth, then place 2-3 drops of the liquid sample to be tested on the prism.then close the cover plate and make sure the water spread aro the prism without any air bubbles or dry spots. wait for about 30 seconds to let the reading to stabilize. Align the prism aembly with the light source. look into eyepiece and you can get the reading. Specification: Measuring Range: Salinity: 0-10% Specific Gravity (SG): 1.000-1.070 Accuracy: Salinity: 1 Specific Gravity (SG): 0.001 Resolution: Salinity: 1 Specific Gravity (SG): 0.001 ATC range: -10~30 C (50~86 F) Dimension: 195x40x40mm Weight: 102g Package Included: 1 x Refractometer 1 x Plastic pipette 1 x Mini Screw Driver 1 x Cleaning Cloth 1 x Plastic Box 1 x Manual in English, French, German, Spanish, Italian, Japanese, Ruian.