JAMIE OLIVER Muffin Tray, Nonstick 12 hole muffin tin with 1 Inch high walls ideal for muffins, cupcakes and Yorkshire puddings Heavy-gauge 0.4mm carbon steel construction on sides and 0.8mm in holes for even heat distribution Durable nonstick Quantum II coating on interior and Xylan coating on exterior keeps food from sticking Thick rolled edges prevent warping even at high temperatures up to 475 degrees F 25 Year Jamie Oliver Guarantee - Hand wash Recommended