The Stablesupport High Profile King Split Foundation set features two Twin XL foundations that together create a sturdy, standard King-size base. With a 9-inch height, this foundation is crafted from high-quality textiles and durable materials to provide lasting support while preventing sagging and bowing. Engineered for optimal mattress performance, it helps maintain the integrity of your sleep surface. Assembled in the USA and backed by a 10-year limited warranty, the Stablesupport King Split Foundation set is designed for durability and peace of mind.