To commemorate the 20th anniversary of John Mayer’s OM-28JM model, Martin Guitars has collaborated again with Mayer to offer two anniversary models: the OMJM John Mayer 20th Anniversary and the OM-45 John Mayer Anniversary. The OMJM is an orchestra model that exhibits the same versatility for today’s contemporary musical styles and includes a unique label with Mayer’s electronic signature. On the OM-45, Mayer’s first signature model with Martin, he included an aluminum border around the headplate and bridge. For this anniversary OM-45 model, the border is expanded to the fingerboard and pickguard and the border has been upgraded to a fine silver.