The Serta iAmerica Historical Firm Collection is designed to give you value for your money. Each mattress is engineered with quality parts to provide a durable sleep system. The Mira-Coil® Innerspring unit is created with 20% more steel with flexible wrapped coils to react individually and gives you a supportive feel. Each mattress has a layer of Gel Active® Foam, a gel-enhanced foam to help provide pressure relief and promote more air flow. A perfect mattress for a guest room in that it will provide a comfortable rest for a variety of sleepers.