This is a full size matress topper ( goes on top of matress ). I have scoliosis ( curviture of the spine ), so I bought this to see if it would help me sleep better. I guess I need something firmer. I have slept on it for four days to try it out. Other than that it's brand new, in great condition & comes with two memory foam pillows. - smoke free home. It's not yellow in the picture, actually white, thats just the lighting, I can send better pics.paid $230 for it