The video: National Lumber By HBSDealer Staff - 10/28/2020 Get great content like this right in your inbox. Subscribe Meet National Lumber of Mansfield, Mass.; the 2020 ProDealer of the Year. Related Content Meet the ProDealer of the Year: National Lumber The Mansfield, Mass.-based business is a family business and a New England powerhouse. At ProDealer Industry Summit, a master course in leadership Kevin Hancock shares from his book on the business of shared leadership.