Designed to be used exclusively with the Green Nest Organic Inner Innerspring Mattresses, the Green Nest Organic Spring Foundation offers superior support for bodyweight ranges of 160-lbs to 275-lbs. A heavy-duty organic cotton cover surrounds the gridlock construction that is anchored to a kiln-dried spruce frame. Features: High gauge steel support coils are covered with a thick quilted organic cotton pad. Specifications: Heavy-Duty Organic Cotton Cover, Kiln-dried Spruce wood frame, Extra-strong gridlock coil construction, 14 gauge wire, and 7.5-inches total foundation height.