Amazon.com: Isellfoam Upholstery Foam Cushion, 3" H x 30" W x 80" L (Medium Firm) 1.8 Density, Compression 36ILD, Seat Replacement, Upholstery Sheet, Foam Padding, CertiPUR-US Certified Foam, Made in USA :
FUTURE FOAM 3 in. Thick Multi-Purpose Foam 10030BULK3 - The Home Depot
FUTURE FOAM 3 inch thick High Density Blue Swirl or Copper Swirl Memory Foam 10030MEMORY3 - The Home Depot
Nova 3" Foam Cushion | Home Medical | Oswald's Pharmacy