PEET Safe Dryer dries unwanted moisture inside the safe by gently raising the temperature inside the safe by circulating warm air through the natural convection process of rising heat and pushing down cold moist air to go through the unit. This process lowers the relative humidity inside the safe helping to keep valuables dry and increase longevity of valuables. This PEET gun safe dryer plugs into the electrical outlet kit (optional on some safes) or 110 outlet.