At the time of their introduction in 1854, Martin “size 0” guitars, with a maximum body width of 13 1/2 inches, were the company’s largest models.

They remained so until the advent of the slightly larger “OO” in 1877, but eventually came to be seen as relatively small instruments, following the introduction of the OMs and Ds in the 1930s. Inevitably, the Os’ modest dimensions restricted their ability to produce big sound, but their sweet timbre and comfortable feel kept them in steady demand, especially among singers.

The company’s new mahogany guitar, the 0-15 was launched in 1940. This was a Spartan-looking flap-top, but it sold well, and remained available until the early 1960s.

This example, as displayed in the title, dates from 1942. The internal stamp on the inside gives the guitar’s model designation and individual serial number.