acrylic, free,, and The molds are great for cooking eggs, baking muffins, cupcakes, and breads, preparing for treats, desserts on a baking sheet, candy making The molds are naturally non stick to make popping out perfectly shaped baked treats a Our cupcake liners are designed to withstand thousands for time ' usage, totally a money saver Easy to clean Microwave, oven, refrigerator, freezer and dishwasher safe