A proprietary formulation consisting of select roofer's flux Asphalt, prime quick-setting VOC-compliant petroleum solvents, reinforcing mini-fibers, and styrene-butadiene-styrene (SBS) rubberized polymers blended to a brush-/squeegee-grade consistency. Irregularities may cause voids, thus inhibiting proper bonding. TAM-Pro 856 adheres SBS-modified bitumen membranes to the substrate (must be smooth), typically a coated fiberGlass Base sheet. 100% Asbestos Free.