The HumidiMeter PRO is the ultimate tool for keeping your cigars fresh. Using state of the art technology to monitor and display the conditions of a humidor. When placed internally in a humidor, the "Cigar Moisture Meter" uses its responsive chip-set to quickly detect the full level of humidity and display it on its digital readout. Simply place it inside and slide its retractable probes with a simple flick of the switch on its back. *Calibration Standard will not work with this model* *Charging cable not included*