Hanna Instruments Groline Quick Cal pH/EC/TDS One-point Calibration Solution 500 mL HI5036-050HI5036 050 is a quick calibration solution for use with Hanna's GroLine pH and or EC TDS meters. Using the Quick Cal function found in compatible meters allows for a single point calibration for pH and or conductivity sensors. Each bottle has the lot number and expiration date. Hanna's line of calibration solutions have been specially formulated to have an expiration of 5 years from the date of manufacture for an unopened bottle. The HI5036 050 is for