Unique in its reliance on natural cotton, this is Royal-Pedics firmest mattress, offering excellent orthopedic support. The mattress features Royal-Pedics double heat-tempered, Royal-Flex® innerspring system designed in Switzerland. The innerspring unit contains 85% more coils than is standard. The coils in the mattress are open ended, unknotted, six turn coils providing more flexibility, which means greater sensitivity to body contours, overall body support and relaxation. Royal-Pedics skilled craftsmen hand layer the staple cotton padding on each side of the innerspring unit to ensure a consistent, supportive sleeping surface. Over 50 pounds of pre-compressed staple cotton go into making a king size Royal-Pedic All Cotton Mattress! No polyurethane foam padding is in the mattress so you have extended durability and lasting support for your body. The inner cotton padding is encased in 100% Belgian cotton ticking, which ventilates body heat. And the mattress is hand tufted the old fashioned way with European tufting straps to further pre-compress the cotton padding for orthopedic back support. Royal-Pedic does not use buttons to tuft their mattresses because buttons have a tendency to turn on their side creating an uncomfortable sleeping surface. The mattress is 8 thick. Dimensions: Twin, 38 in x 75 in; Extra-long Twin, 38 in x 80 in; Full, 53 in x 75 in; Queen, 60 in x 80 in; King, 76 in x 80 in; California King, 72 in x 84 in.