One Sided Mattress Classic® Brecon Firm — A firm-feel supportive 13" mattress with breathable materials, 3 zones for lower back support, and durable coils—plus pressure-relieving upgrades for enhanced comfort Experience the trusted comfort of Serta with Serta® Classic®. Featuring a soft, breathable cover, PillowSoft® Aire foam, and an 800-density coil support system, this mattress helps you sleep comfortably and wake ready to ease into your day. With 3 zones for lower back support, plus a Gel Memory Foam upgrade for even more pressure relief, this mattress balances cool breathability with responsive support and pressure relief for a classically comfortable rest. Designed for a breathable, comfortable sleep Featuring 3 zones for lower back support, breathable fabrics, and responsive coils for classic comfort—plus upgrades available for cooling pressure relief. Breathable Cover A soft, breathable cover helps you rest and wake refreshed 3 Zoned Body Support offers 3 separate zones to provide lower back support for classic comfort A breathable memory foam helps enhance airflow and heat dissipation for a feeling that can only be described as a cool, contouring type of comfort This 800-coil density system provides contouring, cradling support and minimizes motion transfer Layers: Fiber Layer 0.1 in, PillowSoft Aire 1 in, Serta Support Foam 0.5 in, Cool Twist Gel Memory Foam 0.5 in, 3 Zone Body Support 1 in, Serta Balanced Support Foam 1 in, 800 Edition Custom Support Coil System 8 in, Serta Balanced Support 1 in