From Martin:

"With its compact Grand Concert body and all-solid mahogany construction, the 00-15M delivers a warm, intimate sound that fits perfectly in any setting. It features a mahogany top, back, and sides, non-scalloped spruce X-bracing, and a satin finish that gives it a smooth feel and vintage-inspired appearance. The longer 25.4" scale length adds punch and clarity, while the 1 11/16" nut width and Modified Low Oval neck profile offer a comfortable, familiar playing experience. The East Indian rosewood fingerboard includes diamond and square abalone inlays, and nickel open-gear tuners complete the classic look. A softshell case is included, and optional electronics are available for players who want to plug in. Due to material availability, this guitar is designed with either a tortoise pattern or a black pickguard. Selection may vary."

Dark Mahogany, Satin finish, 00-14 Fret body shape, Mahogany top, Multi-stripe Rosette, Non-scalloped X bracing, Modified low oval w/standard taper shaped select hardwood neck, East Indian Rosewood fingerboard with the Abalone short pattern Diamond and Squares position markers, 25.4″ scale length, 1 11/16th” nut width, Open gear strip tuners, With the Martin soft case