High density foam has a compression rate of 36 lbs. This means for every 36 lbs. on a general idea, your foam will compress by 25%. High density foam is designed for that sink in effect for those who love to fall into a nice soft cushion. 100% Recovery rate fire retardant durability : durable, high density foam suitable for long-term use. Our pillow form foam sheets are ideal for a number of projects, such as: Seat Replacement Chair or Sofa Cushion Upholstery Fixing or Replacing Bench Pads and Furniture Boat Seats Upholstery Car & Other Automobiles Seat Repair Home and Commercial Applications DIY Projects, Arts & Crafts Medical Equipments (wheel chairs and walkers)