The RH calibration kit includes the following items: three clear sealable containers, one container with magnesium chloride solution, one container with sodium chloride solution, two wooden scrapers, an insulated carrying case to hold all of the above and maintain a stable environment while performing calibrationThe large container is used to create a stable environment- The small containers are used to hold the saturated salt solution- The saturated salt solutions generate well-defined humidities when they are confined to a contained environment- SKU: NLKL075