Desiccant Moisture Absorbers (4-Pack)One 4 pack (4x132g) is recommended for one mattress bag. Packets are large in size. Our mattress bags are designed to breathe through the seams, providing natural ventilation. For customers wanting extra peace of mind, add our military grade, non toxic clay desiccant pack. They absorb moisture and help prevent mould perfect for long term storage or humid climates, for example. Easy, and effective!