Beautyrest Black® Series Four Medium Firm Summit PT mattress connects luxury, cooling, and support for comfortable sleep. The advanced Triple-Stranded Pocketed Coil® Technology in conjunction with 4K Nano Coils provides enhanced conforming support and motion separation. Premium foams, including Micro Diamond™ Memory Foam and Self-Response latex, with cooling materials closest to you, help provide comfortable luxurious sleep. Invest in yourself and your sleep to feel invigorated as you take on the day.