RC Willey brings you this Sunset Ruby firm twin mattress, a high-quality support at a great low price. The 391 alternating LFK coils are designed to hinge, thus conforming to body shape. They're sturdy and stable and provide great support. It has a firm core loft pad that creates even more support and durability. Have peace of mind with the fire shield, a proprietary blend of natural and synthetic fibers that help isolate the impact of a fire and limit its spread. Proudly made in the USA.