Bostik Black-Top is a liquid, rubber-based, fabric-reinforced, roller-applied, flexible waterproofing and anti-fracture membrane. Use over properly prepared concrete; structurally sound, exterior grade plywood (interior/dry use only); cementitious backer board; and existing, well-bonded ceramic tile or cement terrazzo prior to the installation of ceramic or stone tile. Exceeds ANSI A118.10, ANSI 118.12 and ASTM C-386-89.