Maintenance-free potassium (K⁺) ion-selective electrode for the Roche AVL 9180 and AVL 91xx Series Electrolyte Analysers. Enables precise quantitative measurement of potassium in whole blood, serum, plasma, urine, and dialysate using ISE potentiometry. Flow-through liquid membrane design; no manual filling or reconditioning required. Measuring range: 1.5–15.0 mmol/L. Resolution: 0.01 mmol/L. Content: 1 electrode.