Checkline CP-425 [CP-425-KIT]  Calibration Electrodes For TMT-425 Textile Moisture Meter.The Checkline CP-425 Calibration Electrode is designed for calibration verification of the TMT-425 moisture meter. The kit includes two (2) calibration electrodes, one preset at approx. 22% the other at approx. 44%. The reference value is indicated on the label. To operate, simply insert one of the calibration electrodes into the electrode holder, turn on the TMT-425 and set the calibration curve to "Test Block". The display should match the value printed on the label of the calibration electrode. The calibration electrodes interlock for convenient storage.