The calomel combination electrode is an excellent electrode for clinical laboratory tests and areas with samples containing protein and heavy metals that react with the Ag/AgCl reference cells. The pH range is 0-14 pH. The temperature range is limited (-10° to 80°C). These electrodes are excellent for Tris Buffers. Features: • pH combination • Glass body • General purpose • Single junction • Refillable calomel reference • 8 mm O.D. x 65 mm long reduced portion with removable guard