DeWitt's PRO Flash Xtra Flashing Cement is a rubberized, heavy-trowel consistency asphalt, refined oils, mineral stabilizes, and is reinforced with hi-tech, asbestos-free fibers to make a heavy-duty trowel-grade flashing cement. It can be used on wet or dry surfaces. PRO Flash Xtra Flashing Cement will not sag or slump, thus permitting heavy application on vertical surfaces. It is a tough, flexible, waterproof, corrosive-proof cement that is extra smooth and fast to apply. It is rubberized to perform over a wide range of temperature conditions, eliminating chipping or cracking in cold weather and sliding or bleeding in warm weather.