Happy Tiffins are AISI 201 stainless steel. This steel is lighter, 30% stronger and provides superior corrosion resistance than its counterparts.
The 200 series is austenitic metal. More specifically, ‘201′ is made up of 16-18% chromium, 3.5-5.5 % nickel, 0.15% carbon, and 5.5-7.5% manganese. The 200 series is a high performance stainless steel. The 200 series has a higher tensile strength than the 300 series, which allows it to be thinner. As a result, the 200-series grades are generally stronger and harder than the 300-series. This can be quite significant and useful in some applications. Grade 201, for instance, has a yield strength about 30% higher than grade 304.*
The 300 series is made up of Iron, a maximum of 0.15% carbon, a minimum of 16% chromium and a sufficient amount of nickel and/or manganese to retain an austenitic structure. For example, the most popular in this series, ‘304′ or ‘18/8′ stainless steel means that there is 18% chromium and 8% nickel.
So how to choose?
The '200′ series is the best choice as it is more corrosion resistant, and the fact that it is stronger, therefore items can be thinner; this also makes it much cheaper and lighter. The 200 series is a great option food containers which need to be strong, light in weight and resilient. '300' is a heavy but more corrosive metal and thus not the best choice for food storage containers.