Food-grade salt, purified water and a food-grade thickening agent. Size 8: 2.75″/6.985 cm x 2.5″/6.35 cm. Keep fresh with the Size 1 Boveda. Preserve up to an eighth for months. Use Boveda’s two-way humidity control in smaller airtight jars and bags. It can safely touch your flower, cigars, or coffee and protects against overdrying and mold. People who live in dry climates. People who live in high altitudes. Size 4 is for. Smaller airtight storage containers, including jars and bags.