Bought it for a rather hard/thin RV mattress. It poofed up after sitting on a spare bed for 48 hrs and the smell dissipated quickly. Comfort level has definitely improved from just the mattress, but it doesn't fit the claim of "cooling technology" as I woke up sweating at least half a dozen times. It poofed up after sitting on a spare bed for 48 hrs and the smell dissipated quickly. Oh and not sure how much this matters to people, but I didn't receive the design as in the picture. it wasn't 'rose shapes', it was just alternating chevron, egg crate, and wave patterns in a much lighter blue color. Didn't think to take a photo before I made the bed.