B>Texturized Silica Filament Yarn Woven for Heat Insulation< /B>: < BR>< BR>Insultherm® Silica Header Wrap is made from texturized amorphous silica filament yarn woven into a strong and flexible form. Because the yarn is texturized into a bulky form it provides excellent insulating values.< BR>< BR>Header Wrap SI is not made from leached fiberglass, resulting in a much more wear resistant finished product. Insultherm® Silica Header Wrap is available in Natural.