Versatile – Perfect for both indoor and outdoor use, this raised 16.5" king size air mattress includes a built-in pillow, air pump for convenience, and soft velvety surface for stability and comfort. Strength – Unlike traditional air beds that tend to sink or dip over time, our 16.5" Dura-Beam King Size Air Mattresses have top and bottom ring stability to prevent sagging and maintain shape. Fiber-Tech Beam Construction – Comprised of high-strength polyester fibers, the Fiber-Tech Beam Construction of this king size blow up mattress offers enhanced comfort, stability, and support without sagging. Built-In AC Electric Pump – High-Powered built-in electric pump (110-120V) for quick inflation and deflation; users can easily and quickly set up this king inflatable mattress in about 2.25 minutes. Stretch – After first inflation, the material may stretch and feel like it's losing air. Simply reinflate the king size air bed as needed; it will settle in 2-3 nights.