Hanna Instruments GroLine pH 4.01 Calibration Buffer, 230mL Container Size:500 mL the meter does not need

the meter does not need calibration

doubling the gallon per day output

Approved for use in organic gardening and on edibles

The OA6-110 has 6 separately controlled 120 volt outlets

Hanna Instruments GroLine pH 4.01 Calibration Buffer, 230mL Container Size:500 mL the meter does not needGroLine pH 4. 01 Calibration Buffer is a high quality pH 4. 01 calibration buffer that is NIST traceable and supplied with a Certificate of Analysis. Hanna calibration buffers have the lot number and expiration date clearly marked on the label and are air tight with a tamper proof seal to ensure the quality of the solution. Hanna's line of technical calibration buffers has been specially formulated to have an expiration of 5 years from the date of