Neptune Double Junction probes will out last most other traditional lab grade probes letting you go longer between calibrations, and having to purchase and replace probes less frequently. The Double Junction isolates the reference gel and probe from proteins and other organics that may otherwise precipitate and clog, shortening the lifespan of the probe. Longer lasting Reliable readings Quality connections BNC style connector Neptune's Double Junction pH Probe is compatible with any monitor or controller with a BNC style connection. If you just need to replace your worn out probe or add another you will not be disappointed with the double junction feature of these probes. Most probes have a single chamber to house the actual reference probe and fluid that can become contaminated quickly throwing off readings and requiring calibration quite often. The double junction probes have two chambers that keeps any contaminants that could possibly react with and clog the actual sensing portion of the probe.
