This condiment containers provide an airtight and secure seal to lock in freshness. You can pack your favorite liquids, salad dressing in bags or bento boxes without worry of accidental spills. Dont worry they will stain your bag. Mess-free, spill-free. These containers are made of premium 304 stainless steel, food-grade silicone. BPA free, non-toxic, no chemical odor. It is perfect for outdoor parties, picnics, summer camps and travel. The unique design allows you to open and seal easily without fear of leaks or spills. These sauce containers can be neatly stacked to save more space.