Stay-Put Fitted Fiberbed is filled with luxurious down-like gel fiber that makes it feel like you're sleeping on a cloud. The elasticized fitted skirt keeps the fiberbed anchored to your mattress to eliminate shifting. The super soft, wrinkle-resistant microfiber shell is stuffed with a down alternative for comfort even allergy sufferers can enjoy. The 1-1/2" gusset and box stitching provide superior loft and fill stability.