The Charm Ultra Firm 12" Pocket Coil Mattress by Spring Air is designed for sleepers who prefer a distinctly firm, supportive sleep surface with targeted spinal support and minimal motion transfer. Part of the Spring Air Back Supporter Elite collection , the Charm combines a 5-Zone 8" pocket coil system , high-density foams, zoned gel memory foam, and breathable Tencel fabric. The pocket coil system uses firmer coils through the lumbar area to provide additional support where the body needs it most, while independently responding coils help reduce motion transfer between sleeping partners. The mattress begins with a breathable Tencel fabric cover , complemented by a cushioning silk and wool fibre blend . A layer of firm ECOTEX™ gel foam contributes cooling, support, and durability, while extra-firm high-density foam reinforces the mattress's ultra-firm feel. A ½" zoned gel memory foam layer provides additional pressure-point relief and contouring. At its core, the 5-Zone 8" 1,200-count pocket coil system is designed for pressure relief, reduced motion transfer, and enhanced lumbar support. A Foam Encased Solid Sleep Edge provides stable edge support and helps maximize the usable sleeping surface. At 12 inches high with a Tight Top construction and Ultra Firm comfort level, the Charm is purpose-built for customers looking for a firmer sleep experience. It is also adjustable-base friendly, CertiPUR-US certified, and proudly made in Canada . Available in Single, Double, Queen, and King sizes under one convenient product listing. NOTE:   Canadian/ custom-made with production time around 10-15 days