... 2.Ne203,303,403 3.permanent flame retardant Aramid Sewing ThreadDescriptions: 1) Composition: 100%meta-aramid.2) Specification: 203, 303,403 etc.3 ... for ten years above.5) This meta-aramid sewing thread is mainly used in sewing the filter bags, protective clothing, FR decoration, high ... certificate, OEKO-TEX100,EN469, etc.7) similar to NOMEX 100% Meta Aramid Sewing Thread