portable Refractometer

Product highlight ·Accurate test result, easy to read ·Able to calibrate ·A must have for people with marine aquarium tank Product dimension - In The Box ·Refractometer with standard accessories Instruction of use Usage:
1 Open the cap
2 Use dropper, drop a few drops of water sample on to the glass
3 Cover the cap slowly to avoid producing any bubbles
4 Look into eyepiece to get result
Calibration:
1 Prepare RO or distilled water(not included)
2 Drop a few drops of RO or distilled water on the glass
3 Cover the cap slowly to avoid producing any bubbles
4 Look into the eyepiece
5 Use the screwdriver provided, adjust the reading(RO or distilled water should be 0 salinity) Tips & Tricks ·Make sure there is sufficient light while using refractometer