Experience the best of Beautyrest®, featuring advanced temperature management technology, Micro Diamond™ Memory Foam, and advanced, Triple-Stranded Pocketed Coil® Technology for conforming support and motion separation. Self-Response™ Latex offers a specialized upgrade for responsive pressure relief, as it contours to relieve your body’s unique pressure points while maximizing airflow for cool sleep every night. Plus, for an even more luxurious upgrade, Series Three Pillow Top models feature exclusive 2K Nano Coils for enhanced, individualized support throughout the night. With the inclusion of premier materials and advanced sleep technology, Beautyrest Black® optimally aligns at the intersection of luxury and innovation for an extraordinarily comfortable sleep. For the person who wants an ultra-supportive, firm feel with no sinking feeling  Triple-Stranded Pocketed Coil® Technology offers our most advanced level of individualized support and motion separation, so you can rest undisturbed  Cooling yarn and cashmere woven into the mattress surface, tops a layer of specialized vertical fibers in an advanced feature designed to help transfer heat away from the body all night A layer of specialized foam is quilted into the sleep surface to unlock immediate, advanced pressure relief Premium memory foam layer, infused with diamond particles, is designed to help move heat away from the body for a cool slee Ventilated latex layer maximizes airflow while contouring and conforming to your body for responsive pressure relief Specifically designed to work together with your Beautyrest Black® mattress, this 9" Beautyrest Black® foundation offers long-lasting support and reduced motion for restful night’s sleep  Mattress Top Type: Tight Top Mattress Type: Innerspring Included: 1 Mattress(es), 1 Box Spring(s) Features: Foam Layer, Cushioning Layer, Temperature Regulating, Wrapped Coils, Full Support, Cooling Layer Additional Information: Eliminates Motion Transfer, Conforms To Body, Relieves Pressure Points, Suitable for Adjustable Bed Frames Coil Count: 696 Coils Manufacturer Warranty: 10 Year Limited Bed Size: Twin Xl Measurements: 38 Width/Inches, 80 Length/Inches, 14.25 Height/Inches Maximum Weight Limit: 850 Lbs Base Material: 70% Polyurethane, 30% Metal Comfort Type: Extra Firm Mattress + Box Spring Measurements: 80 Length/Inches, 38 Width/Inches, 23.25 Height/Inches Care: Spot Clean Certifications And Listings: Certipur-Us Certified Mattress Height: 14.25" Country of Origin: Made in US Set includes mattress plus box spring/foundation. King and Cal. King mattress sets feature 2-piece side-by-side foundations for easier navigation in tight spaces.