The thick microfiber towel/sponge is sewn with silver yarn. The drying mat drains water from the glasses and decanters that you just hand-washed under warm water. The direct contact with the silver yarns purifies the rim of the glass and the entire glass is wiped with the mat. The mat has the following attributes: extremely absorbent, prevents water stains, does not leave any material residue and is ecological and durable.