Hanna HI12943 Direct Soil pH Electrode Triple Junction Probe for HI9814 Meter chrome faucet the 201 C requires no electrolyte colorimeter reagents the 201 C requires no electrolyte refilling MA9066 is a lab grade 100% NaCl (EC) solution standard prepared against a NIST traceable potassium chloride solution that allows you to recalibrate your conductivity meter or tester providing an electrolyte flow rate of 40 50 µL hour—more than double the 15 20 µL hour flow of standard single junction electrodes The refillable design allows you to maintain optimal electrode performance by replenishing the reference electrolyte as needed