Please put the gel mattress topper flatly in a ventilated area for 24~36 hours until fully expanded. Don?t forget to rotate the foam topper every two months to enhance the lifespan of it. Manual measurement has been used there may be some reasonable error. Please confirm the product size before purchasing to make sure the size of our product is in line with your requirements. Items may slightly differ from photo in terms of color due to the lighting or your monitor?s display. Pictures taken with professional equipment for reference only. Best specification: Item Display Height:2.0 Inches ---It is also very suitable for who are side sleepers and patients with joint pain. ---Designed to be placed right on top of your current mattress for an added comfort layer. ---Correctly aligns the spine by supporting the head neck and shoulders. ---Specialized memory foam is soft. Infused with temperature-controlling gel to help distribute heat across your mattress. Memory Foam Mattress Topper Topper Foam Toppers M