6-Spot Humidity Indicator Cards

Humidity indicator cards are printed with moisture sensitive spots which respond to various levels of humidity with visible color change from blue to pink. Place inside vacuum sealed moisture barrier bags to monitor the interior humidity conditions. When the bag is opened the card can be examined for proper dryness inside the bag. Card monitors humidity levels from a range of 60% to 10%. Card size 1.56" x 4.75". Packaged 200 cards per can.