wool felt performance standards: GB FZ/T25001-92.The wool felt products are made from raw wool. Felted wool is used in mechanism, aviation, shipping, train, auto, metallurgy, chemical, industry, textileindustry, seal, dustproof, cushion, quakeproof, heat preservation,heatproof,sound insulation, fire retardant,insulation.Filtration:air,petroleum,waterPolishing:marble,crystal,glass,jadeware, ...