Elevate your sleep to a luxurious reward night after night. As a part of our most advanced collection yet, Beautyrest black® l-class offers up to 21% more support where your body needs it the most with help from our new plant-based cooling technology, the collection provides up to 18% more cooling power to keep you comfortable as you fall asleep and all night long in addition, our patented memory foams unlock immediate pressure relief and personalized support. These innovative features are paired with an all-new modern design to create a first-class sleep experience that will leave you feeling invigorated to take on your day.  Mattress Top Type: Tight Top Mattress Type: Innerspring Included: 1 Mattress(es), 1 Box Spring(s) Features: Cooling, Foam Layer, Cooling Layer, Non-Toxic, Full Support, Cushioning Layer, Temperature Regulating, Antimicrobial, Wrapped Coils Additional Information: Suitable for Adjustable Bed Frames, Relieves Pressure Points, Conforms To Body, Eliminates Motion Transfer Coil Count: 513 Coils Manufacturer Warranty: 10 Year Bed Size: Twin Xl Maximum Weight Limit: 1000 Lbs Base Material: 50% Wood, 50% Metal Comfort Type: Firm Mattress + Box Spring Measurements: 79.5 Length/Inches, 39 Width/Inches, 22.75 Depth/Inches Care: Spot Clean Certifications And Listings: Certipur-Us Certified Country of Origin: Made in US Visit our Furniture & Mattress Customer Care Center for delivery options, protection plans and other services. Problem with an order or need help with a return? Our Furniture & Mattress Customer Service agents will be happy to help. Give us a call at 1-800-442-7902 Don’t forget to print off your delivery checklist to avoid any delays or issues when delivering your item. 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.