BDC 8400 Pebble Bond is a two component, 100% solids, low viscosity, moisture tolerant, high strength epoxy formulated specifically for the bonding of natural river stones to structural substrates. Our trusted and proven system has been on the market for over 30 years with great success. Pebble Bond is specially formulated to allow for incredible drainability, while still being very durable, stain resistant and crack resistant. B.D. Classic also has a special U.V. Resistant formula available by special request.