The ZINUS 9 Inch Metal Smart Box Spring Mattress Foundation is a sturdy and supportive foundation designed for a King-sized mattress. It features a strong metal frame in a classic black color, with a firmness level that provides optimal support for a comfortable night’s sleep. The box spring is rectangular in shape and measures 9 inches in thickness, making it suitable for most standard-sized mattresses. With a weight of 45 lbs., this lightweight and easy-to-use foundation is perfect for both men and women, and can seamlessly enhance any bedroom decor with its simple yet effective design.