The 4-inch seat uses dense, USA-made foam that keeps its shape and delivers long-term comfort. Our upholstery meets CAL 117 flammability standards, are GREENGUARD certified, and comply with California Section 01350 for low chemical emissions. The cushioned seat contains no PBDE flame retardants and is free of PFAS chemicals, reflecting our commitment to safety, compliance, and responsible material use in furniture applications.