Rubberized Under Coating POR-15® Rubberized Under Coating is a flexible, paintable, black coating. It is the only undercoating with POR-15® Technology and will protect against moisture, dust, heat and cold. It's an excellent moisture barrier for application over auto body repairs and creates an effective sound barrier that reduces vibration and deadens sound in wheel wells, quarter panels, fenders and under carriages. Provides superior adhesion to both painted and unpainted surfaces. POR-15® Rubberized Under Coating has superior resistance to road salt and will resist chipping and abrasions. May be used to insulate against engine and muffler noise, protects against dust penetration and exhaust fumes. POR-15® Rubberized Under Coating may also be used on the inside of house gutters and over flashing. Also can be used as a tree dressing after pruning to slow further growth in that area. POR-15® Rubberized Under Coating can be applied directly over POR-15® Rust Preventive Paint for the toughest rust, corrosion and moisture barrier possible along with excellent sound and vibration deadening.