Kit includes the R9933 (Humidity Calibration Standard, 33%) and R9975 (Humidity Calibration Standard, 75%). For use with REED R6001, R6200, SD-3007, R9900 and 8706. REED R9980 Offers Features ± 1% Accuracy (at 77°F (25 °C)) Compatible with probes with a diameter up to 0.6" (15mm) Included N/A