Features: 1.Perfectly test the salinity and specific gravity of brackish water and marine fish tanks, including the solubility and specific gravity scale. 2.The safety zone is clearly marked, the outer range of the scale indicates salinity (PPT), and the inner range of the scale indicates gravity. 3.Use range: 0?40 degrees (1.000?1.030). If the salinity ppt is between 32?40, it means that the salinity meter is high; if the salinity ppt is between 27?31, it means the salinity meter is normal; if the salinity ppt is between 0?26, it means that The salinity scale is very low. 4.It has a wide range of uses, suitable for brackish water and marine fish tanks. Suitable for fresh water and sea water. 5.Made of high quality plastic material, corrosion-resistant, not easy to damage, durable and safe to use. Specification: Condition: 100% Brand New Item Type: Sea Hydrometer Material: Plastic Body Size (LxWxH): Approx. 13 x 9.1 x 1.7cm/5.1 x 3.6 x 0.7in Rod: Length: Approx. 14cm/5.5in, Diameter: Approx. 0.3cm/0.1in Suitable Type: Suitable for brackish water and marine fish tanks. Function: Dedicated test concentration Application Method: 1. Insert the hydrometer below 15cm to prevent pollutants such as oil film from affecting the accuracy of the test 2. When the water is full (level with the top of the baffle), take out the hydrometer and place it on a level surface 3. Air bubbles attached to the pointer will cause inaccurate readings. Carefully tap the hydrometer to shake out the attached air bubbles. 4. Get the reading of the hydrometer, the reading of the oceanarium should be between 1.021 and 1.023. The reading of the aquarium should be between 1.024 and 1.026. 5. Use the hydrometer in water with a temperature range of 68-86 (20-30). 6. Clean the hydrometer after each use. The remaining salt crystals in the hydrometer will affect its accuracy. Soak the hydrometer in warm water for 30 minutes, then rinse with water to remove salt crystals PackageList: 1 x Sea Hydrometer 1 x Rod 1 x Manual