Products / Malarkey 420 OmniSeal Ply

420 OmniSeal Ply is Malarkey's self-adhering SBS polymer-modified fiberglass sheet, used as a base or ply sheet in self-adhering and torch low-slope systems without mechanical attachment. It has a primed top surface and a self-adhering compound underneath under a split release film. The data sheet gives a 39-3/8 in. by 66 ft. roll (2 squares), 60 mils nominal, 80 lbs. per roll and a perm rating of 0.1 or less, and says Malarkey treats it as a Class I vapor retarder listed as such in FM Approved assemblies. It lists ASTM D1970, ASTM D4601 and a Class B and C fire rating to ASTM E108, and refers warranty terms to Malarkey.