Food-grade material, can be in direct contact with food, safe to use Vacuum the air valve to extract the air in the tank to keep moisture, prevent mildew and insects, and reduce the oxidation rate Time compass, record the date of initial fresh-keeping test, convenient to calculate the storage days Simple operation, physical vacuum lock freshness Double-sided strong lock buckle, fastening and , firmly buckle, thickened silicone sealing ring, detachable and easy to clean