I bought these cushions to replace the foam in my cushion covers from my 1960's sofa. They fit perfectly. They added height to the back of my sofa (but that is mainly because my other cushions were so old they had sunk/collapsed over time and I didn't really realize). My sofa looks new again. They had no noticeable odor and I let them sit open for a few days before placing the cushion covers on. They are a bit on the firm side but I figured they would last longer and provide the needed support. After reading some reviews about the "Firm" pillows I decided not to risk it being too soft and went with the Extra Firm. I will put a few soft accent pillows in front and call it a day.