Indicates the main composition of the mattress, such as innerspring or memory foam. Some so-called "hybrid" innersprings include one or more levels of foam on top.

If you’re looking for a replacement, over 5,200 Walmart shoppers swear by these never-flat Serta ... Pillow is made of a cotton and polyester blend and has a foam core surrounded by plush ...

A combination of characteristics analyzing user interaction with the pillow, including attributes such as panel judgments, head contact, and pressure distribution. The Serta StayCool Gel Memory ...