APCI Capillary Electrode, API 4000, API 5000, 4500 Back Catalog number: CTS-21102 Availability: In the manufacturer's stock Price on request - + Recommended MW600 Dissolved oxygen meter MW600 Price on request MW802 Smart pH/EC/TDS combined meter MW802 Price on request EC59 EC/TDS/Temp waterproof tester EC59 Price on request