The Orion Star A and Versa Star electrode holder head has identifiable slots and offers the following benefits:

Orion™ Star A Series Electrode Holder for Electrode StandsUse the Thermo Scientific™ Orion™ Star A Series Electrode Holder with a meter-attached or swing arm electrode stand to organize your sensors for easier movement in and out of samples and simplified rinsing and storage. The electrode holder accepts up to six sensors using 12mm holder with optional ATC probe insert, 20° angle holder for gas sensing ISEs, 15mm holder for conductivity and DO probes, 12mm flex clip holder for pH, ORP and ion selective electrodes, center stirrer probe holder and removable RDO probe holder. The Orion Star A and Versa Star electrode holder head has identifiable slots and offers the following benefits: Adjustable probe heights reduce the amount of sample needed for testing Easy removal from clips enables easier electrode maintenance and saves time The 20° angle position for gas-sensing ISEs makes it easier to keep bubbles off the sensor for accurate readings Dedicated stirrer port for Orion Star stirrer probe aids in quick and easy sample mixing Fixed front slot works with ATC probes (using the included adapter) or other 12mm dia probes Use to update existing swing arm stands (090043) or as a replacement electrode head on the Orion Star A and Versa Star electrode arm and holder (STARA-BEA). Includes: Redesigned electrode holder head, ATC probe adapter and RDO probe clip Requires: Electrode arm and base (attached to meter or separate) For Use With: Electrode ArmDescription: Electrode Holder HeadIncludes: Redesigned electrode holder for up to six electrodes and sensors (purchase stand and base separately)Item Description: Orion Electrode Holder Head with ATC probe adapter and RDO probe clipType: Electrode stand/holder more