When you need maximum coverage and maximum sealing power, take your projects to the maximum. Our new FLEX SEAL maximum is our most economical option, covering up to 20% more than our original size. FLEX SEAL maximum is a rubberized sealant spray coating that sprays out as a liquid. FLEX SEAL maximum seeps into cracks and holes and dries to a watertight, flexible coating. It's the easy way to coat, seal and stop leaks fast. Color: Clear.