Review on Durable Professional Half Sheet Baking Pans - Set of 2 Aluminum Cookie Sheets - Oven-safe, Non-toxic, Easy to Clean - Commercial Quality - 18x13-inch Rimmed Baking Sheets for Baking and Roasting by Debbie Rossi

I bought these because I wanted sheets that could withstand over 450°F (most were at or below) and not rust. I searched and searched and finally settled on them because they claimed they never rust and had the right heat range. When I received them I was concerned because the packaging said the rim was reinforced with steel but the answers the seller gave to other people about washing dishes was that the only concern was aluminum discoloration so I hoped that my fears were unfounded. I was really hoping they would stay rust free in the dishwasher. However, I hand washed both of them beforehand. I then used one of these and hand washed it again. So one had a wash and the other had two and they were both hand washed and had rust on the underside under the folded lip.