Sodium calibration solution or calibration standard is needed to calibrate meters for extra precision.
This sodium 150 ppm calibration solution will last up to 300 calibrations of LAQUAtwin meters. Great for calibrating sodium ion meters. Equivalent solution of HORIBA calibration solution Y022L. 
We recommend calibrating your LAQUAtwin meters daily (if you measure daily) or after every 10 measurements within a single day if you are testing more intensively.
 
⚫ Volume: 60 ml bottle with a twist top cap
⚫ Standard solution concentration: 150 ppm (150 mg/L) of Sodium (Na+)
⚫ Compatible with HORIBA LAQUAtwin Na-11 and B-722
⚫ Made in USA