PermaFlash Scrim is a stitchbonded polyester scrim that offers a sturdy combination of burst strength and toughness for roofing applications. PermaFlash Scrim is part of the PermaFlash System - an integrated flashing system specially formulated for use in bituminous roofing systems. The PermaFlash System also includes PermaFlash™ Primer and MBR® Flashing Cement.