This set of items are made of strong, heavy-duty carbon steel, they evenly disperse heat and weight for a consistently good bake, which is for baking and cookie. In addition, it won't rust like zinc and alloy. This will quickly become one of your favorite kitchen gadgets. Features - Color: As shown. - Size: 37 x 25.5 x 1.6cm. - Material: Carbon steel. - Crafted from high-quality food safe carbon steel, non stick and safe to use. - This set of cookie sheets is lightweight and flexible. - Super easy to clean up. Just rinse under water or run through the dishwasher. - Won't rust or break over the time It will last for years in your kitchen. - for baking or cooking, great in toaster ovens, RV ovens, small portions in conventional ovens or freezer.