The Thermos Compact Stainless Steel Food Jar is designed with durability, as well as functional performance in mind. These leak-proof food storage bottles are constructed from 18-8 grade vacuum insulated double wall stainless steel for years of insulation performance. Wide mouth opening allows for easy access, as well as easy cleaning. The bottle lid has an ergonomic design for easy access, and the base has a skid proof bottom to insure stability, and reduces scratches that may be caused with similar bottles. These are very nice units indeed!