The Winncom Firm mattress features Serta’s Cool Twist® Gel Foam and new 739 Custom Support® Firm Individually Wrapped Coil System. It is designed with a unique set of features to help solve 5 common sleep problems*: 1. Helps reduce tossing and turning with Cool Twist® Gel Foam 2. Encourages proper back support and alignment with Serta’s new 739 Custom Support® Firm Individually Wrapped Coil System 3. Promotes a balanced sleep temperature with an overall mattress design that helps promote airflow4. Minimizes impact from partner movement with a premium support system and advanced foams designed for motion isolation5. Resists sagging and edge roll-off with Serta’s ComfortLast® Construction and Best Edge® Foam EncasementA special innerspring coil gauge design helps create a firmer feel across the mattress when compared to the Winncom Plush. This mattress is compatible with a Serta adjustable foundation.