Here to remind you why you fell in love with Martins in the first place, the new Authentics are constructed in 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 1939 D-18 in the Martin museum, this guitar features genuine mahogany back and sides, an Adirondack spruce top, and an authentic circa-1939 bracing pattern. Period-correct "18" Authentic-style appointments with an Authentic neck barrel and heel complete this piece. Martin’s new Vintage Tone System (VTS) is employed for the top and braces. Specs: Make: Martin Model: D18 Authentic 1939 Body Size: D-14 Fret Construction: Dovetail Neck Joint, Hide Glue Bracing: Scalloped, Rearward Shifted X Bracing, Adirondack Spruce Top Wood: Adirondack Spruce with VTS Back and Side Wood: Mahogany Finish: Vintage Gloss Scale Length: 25.4” Nut Width: 1 11/16” Neck Shape: Authentic 1939 Neck Taper: Standard Taper Binding: Faux Tortoise Top Inlay: Multi Stripe Pickguard: Faux Tortoise Rosette: Old Style 18 Multi Stripe Bridge: Authentic Belly, Ebony Saddle: Glue In Long Saddle, Bone Bridge Pins: Plastic Back Strip: Madagascar Rosewood Neck Wood: Mahogany Neck Finish: Vintage Gloss Fingerboard: Ebony Frets: 20 Fingerboard Inlay: Old Style 18, Abalone Fingerboard Binding: None Tuning Machines: Nickel Open Gear, Butterbean Knobs Nut Material: Bone Case: Martin Ply Hardshell