BVV™ Molecular Sieve Beads Type 4A - 308LBMolecular Sieve Beads Type 4A This bag contains both blue moisture indicating molecular sieve and also normal molecular sieve. The blue molecular sieve is a sodium alumina silicate molecular sieve impregnated with an inorganic metal salt moisture indicator. The desiccant will perform as a 4a molecular sieve plus with the additional ability to visually determine when the molecular sieve reaches saturation. When active, the molecular sieve beads are