879-18 is a tough, finely woven nylon fabric treated with a release agent. It is used to separate the absorber, breather, and vacuum bag from the laminate in vacuum bagging operations. Excess epoxy bleeds through and is peeled from the cured laminate along with this fabric, which may also be referred to as peel ply. It’s also used in hand lay-up applications to allow more squeegee pressure and protect the lay-up from contamination. Peels easily and leaves a smooth textured surface, ready for bonding, sanding or finishing. Not recommended for post-cure temperatures over 120°F (49°C)