The Best Stainless Steel for Stainless Steel sinks is Certified 304-grade steel.
304 Stainless Steel has 18% Chromium and 8% Nickel. The Chromium gives the sink its luster and it will match the kitchen appliances which are also made from 304-grade stainless steel. The Nickel hardens the finish so it does not age. Here is an excerpt from a presentation we did for one of our customers.
https://youtu.be/WslYltUzaCo