This non-stick cookie sheet is ideal for baking cookies and biscuits. An insulated air pocket in the baking sheet helps protect your baked goods from intense heat, giving you a perfect even bake. So no matter if you're looking to create the tastiest crisp lemon shortbread or the gooiest chocolate cookie, this baking sheet has you covered. Reasons to choose the Circulon Ultimum cookie sheet: Ultra Hi-Low Non-Stick System. Baked foods release with ease and cleanup is effortless. Perfect, even baking performance. Insulated air pocket protects baked goods from intense heat, resulting in even browning. Ideal for heating food from frozen. Limited Lifetime Guarantee. Technical specification: Material: Carbon Steel Measurements: 40.5cm x 35.5cm x 2.5cm Oven Safe: 230°C/450°C/Gas Mark 8 Non-stick: Yes Dishwasher safe: Yes