Pre-measured refractometer calibration solution takes the guesswork out of properly calibrating your instrument - with no need for expensive or unreliable measuring equipment. A refractometer is essential to the saltwater hobbyist for success. Maintain its accuracy by recalibrating regularly.

Adjust calibration mechanism to read to one of the following specifications:

35 ppt
1.0264 Specific Gravity
1.3394 Refractive Index
53 uS/cm at 25 deg C