It are designed to securely fit crucibles with a 35mm diameter, providing an essential tool for high-temperature applications in laboratory environments. Made from durable porcelain, these lids offer excellent resistance to heat and chemicals, making them ideal for use in heating, calcining, or melting experiments. The 39mm diameter ensures a snug fit, helping to prevent spills and maintain sample integrity during processing. This pack of 5 lids provides a cost-effective solution for laboratories requiring high-quality crucible accessories.