The American Barn offers the long-lasting S&K design that you've seen so often. It's a barn with a country flair. It offers 12 compartments for a full-sized martin colony. The nesting area is textured, has a water dam, and shaped to allow quick water drainage. It's made for the RP19 (1.9" diameter round pole), a SP2 (2" Square Pole), The Ez-lift 2 3/8" pole (2 3/8" diameter round pole), or the Triangle Poles (Quad-Tel or Tri-Tel Pole). The American Barn can be used with a TTP /QTP/1.25 O.D. Round Pole with the purchase of the RTPAS (Round Triangle Pole Adapter Set) and the purchase of a new roof. The RTPAS snaps into the bottom of the floors and then attaches to the triangle poles or 1.25- inch O.D. Round Pole. RTPAS (Round - Triangle Pole Adapter Set) is Sold Separately S&K Manufacturing, Inc. AB is constructed of 100% UV Protected Injected Molded Polypropylene Copolymer Plastic. AB Includes the following: - 12 large compartments 6"x 9" - Entry Doors are Starling Resistant - The AB is EXPANDABLE to include multiple floors by adding additional houses. . - New House Snap/Screws (black in color)