Description Product Description Here to remind you why you fell in love with Martin in the first place, the Authentics are constructed the old way - with hide glue, throughout, and historically-accurate detailing confirmed by using a CAT scan machine located at the Smithsonian Institute. Based on a 1941 D-28 in their museum, this guitar features Madagascar rosewood back and sides, an Adirondack spruce top, and authentic 1941 D-28 appointments, right down to the neck barrel, heel, diamond, head taper, and slots.