ADD one shop spray coat standard sound dampening and one coat Aquaplas premium sound dampening to the exterior of a single offset up to 4 feet long. While not usually sufficient to require additional work, please note that sound dampening will suffer some damage in shipping so you may want to consider applying yourself on site rather than pre-applied. Click here for a supply of standard sound dampening and here for a supply of premium sound dampening sufficient for this size offset to be applied by customer. Additional sound dampening product is available should it be required for touch-ups. See attached spec's for this product before ordering.