The Calphalon Commercial 2.5 Quart Double Boiler Insert G102 1/2HC is a vintage yet original piece of cookware made in the USA. This round, gray aluminum double boiler insert is designed for use with electric and gas stoves, making it versatile for various cooking needs. With the Calphalon brand backing it, this high-quality kitchen essential is a must-have for collectors and cooking enthusiasts alike.