ECFG4390401B Glass-body pH Combination Micro-Electrode, reference Calomel Refillable ,4x55 mm, BNC connector, 1m cable length .Ideal for Micro sample, such as semi-micro cuvettes and NMR tube, Research measurements, fruit juices, beer, milk and yogurt,Tris buffers, clinical, and biological media containing proteins, creams, fats and cosmetics