Not too firm and not too plush, the iComfort CF1000 medium mattress is just right. With the iComfort by Serta mattress, cool, supportive sleep is the priority. We’ve specifically designed this mattress to keep even the warmest sleepers cool. With iComfort, multi-layered mattress-cooling foam technology adds support, resilience, and temperature regulation for the coolest, most comfortable sleep ever. You don’t have to be a hot sleeper to love iComfort. You just have to like your sleep environment to be refreshingly comfy.