Check the listing for details. MONO M80 Classical/OM Case Jet Black. Color: Jet Black, Condition: New with tags. Listed at 279.99 USD. Lke the rest of the M80 Series Mono Cases, the M80-AC Classical/OM case is designed from the inside out to be one of the lightest, thinnest, strongest, and most versatile carrying solutions for the professional musician. A hybrid case featuring an ultra-light laminated foam shell with strategically placed ABS panels, the M80 Classical/OM Case provides an extremely high level of protection for your most-prized investments. Smart features like the Clip/Tuck straps make for easy airport travel, while the streamlined profile helps you slip through the crowds.Slightly more compact, the M80-AC is designed to fit smaller body classical, OM and 000 style acoustic guitars, like the Martin OM, Collings C10, Larrivee OM, Yamaha Classical models and others.