Question about Gastroback Vacuuming containers

Vacuum container set in three sizes: 0.75 litre, 1.4 litre and 2.0 litre for your vacuum cleaner. When vacuumed, your salads and other pressure-sensitive (mushrooms, tomatoes) or very moist foods (soups, sauces) stay fresh up to eight times longer. Rely on natural freshness, because storage in the absence of air requires no preservatives. The shatterproof and dishwasher-safe containers are made of robust styrene acrylonitrile, the lids of ABS plastic and can be reused as often as you like - a worthwhile investment. With vacuum hose, suitable for the Caso vacuum cleaner.
Also available at the supermarket. Simply cheaper