Tested at the Bat SanctuaryBat behavioral expert, Amanda Lollar, designed this unique house. Tested and approved by the occupants of her bat sanctuary, this house features two chambers and a slot opening at the bottom, a large landing platform, screened interior and echo-location slots on the sides to help the bats locate the hollow cavity. Suitable for all species of small, insectivorous bats. The various widths determine maximum size of colony.Large Sunshine houses up to 300 batsHand ConstructedHand constructed of eastern white pine, (which is environmentally preferred) and is designed with a unique roughened surface, which bats can easily cling to. Solid construction provides warmth, insulation and durability. Opens at the bottom so it needs no cleaning and birds will not nest in it.Note: Due to weight of product, expedited shipping is not available.