Parksite Tyvek Flexwrap NF 6 in. x 75 ft. superior air resistance to help prevent the flow of air through wall cavities and reduce drafts, enhancing your building's energy efficiency. This product also provides excellent moisture resistance to protect the wall cavity from water that may get behind the cladding, while its moisture vapor permeability promotes the drying of wall systems to prevent damage. Designed for durability, it can withstand the rigors of construction sites and continue performing effectively once construction is complete. This high-performance, 100 percent butyl-backed, extendable self-adhered flashing material is i for use on sills, heads, and penetrations. Additionally, it boasts 9 months of UV resistance, ensuring long-lasting protection during installation.