MALOUF ISOLUS Plush Down Alternative Fiber Bed Mattress Topper with Pure Cotton Cover - King 3 inch thick mattress topper with hypoallergenic down alternative fill 250 thread count 100% cotton shell Baffle box stitching that improves breathability and keeps fill from shifting Thick corner elastic anchor bands secure fiberbed to mattress King fiberbed measures 76" x 80" and comes with a 3-year U.S. warranty