3M Humidity Indicator Cards are printed with moisture sensitive spots which respond to various levels of humidity with a visible color change from blue to pink.
3M Humidity Indicator Cards are used inside vacuum sealed (dry packed) moisture barrier bags to monitor the interior humidity conditions of the package.
When the bag is opened, the card can be examined to verify proper dryness inside the bag.
This indicates that the moisture barrier bag and desiccant functioned correctly.
Performance tested. Lot traceable. RoHS Compliant and lead-free.
