A rubberized butyl-backed, self adhering membrane flashing tape designed to provide a long term weather tight seal to prevent moisture, vapor and air penetration around windows and doors.
OSI Butyl Flash is part of the OSI QUAD Window & Door System and is used to provide an air and vapor barrier around window and door flanges and joints and cracks in exterior wall assemblies. It is also useful for other above grade wall flashing applications.
Concrete, masonry and some exterior gypsum substrates may require priming for best results. Do not apply orimier or flashing to damp, frosty or contaminated surfaces.