Honeycomb structure cushion with excellent breathability. It disperses body pressure, making it less tiring to sit for long periods. The cover is made of mesh fabric with a non-slip backing, making it less likely to slip. I purchased a set of two, but I'm selling one because I don't use it. Although unused, it has been stored in a closet for about two years, so I have washed the cover just in case. Please refrain from purchasing if you are concerned. There are no boxes or bags, so please understand that it will be shipped in simple packaging. Please refer to photo number 5 for the size. Thank you for looking.