These are glass storage containers from the German glass manufacturer WECK. WECK is a long-established brand founded in 1900, and has been loved for over 100 years. They can be used for storing food items such as jams, pickles, and coffee beans, as well as for serving drinks, making gratins, and baking. Although they are not heat-resistant glass according to Japanese standards, they can be used in a water bath, oven, and microwave if sudden cooling and heating are avoided (temperature difference resistance within 80°C). Size: 50ml, 6 pieces 70mm x 40mm Stored at home, unused. Six unopened sets of rubber rings and clips are also included. They are mini size and cute. The price will be gradually reduced, so please refrain from negotiating.