It removes mold stains from breglass, rubber and sky (boats, inflatable boats and cushions). Sodium hypochlorite based product, Shmuffex is not suitable for fabric because it may damage it. DIRECTIONS FOR USE: First of all, remove any excess soiling not due to mold; then spray product directly onto the surface to be cleaned; let stand until mold stains disappear and then rinse with water. The length of time for treatment will vary, depending on the type and severity of mildew. If necessary, leave on for an hour, or apply the product several times in order to get the desired result.