pocket springs mattress DIY structure: Cover: High Grade Knitting Fabric, Jacquard Fabric with Spray-bonded Cotton. Super soft Foam with Non-Woven Fabric. Latex or memory foam. Middle: Super soft Foam covered Cotton Felt. Pocket Springs units made of high carbon manganese steel wire in DIY size, with Steel or Foam Frame. Bottom: High density Non-Woven Fabric with foam or Spray-bonded Cotton. Approved ISO 9001: 2000, Compression Resistance 80000 Times. Guarantee 10-12 Years. OEM. Fire-Retardant, TB603, CFR1633, BS7177, BS5852.