These guitars have a relatively smaller body than the Dreadnoughts and Jumbos that appeared later in history.

They could generally be categorized into the Grand Concert body size, comparable, or even identical to Martin's 00-style guitars.

[2] with spruce top and, in the beginning of their production, employed either X, H, or A bracing patterns.

Later the body shape was widened to 14+3⁄4 in (370 mm) with a more squarish bottom, quite analogous to Martin's 00-style guitars.

This guitar is designed for the Century of Progress International Exhibition hosted in Chicago.

It featured celluloid plastic ("pearloid", or "mother-of-toilet-seat") covered fretboard, because back in those days this material was considered modern.

Gibson also made HG-0, HG-00 and HG-C during 1937 to 1942, which were practically Hawaiian variants of the corresponding L models.

[6] The Nick Lucas model was first introduced in 1927, as the first artist endorsed Gibson guitar, and a high-end, deep-body version of L-1 (about 4+1⁄2 to 4+3⁄8 in (110 to 110 mm) deep[3]).

Late models of B-25 and B-25N have adjustable saddles equipped, just like many other '60s Gibson acoustic guitars.

It was listed as a "student model" by Gibson, with spruce top and laminated mahogany back and side.

It's worth mentioning that there is also a model B-45-12 in the B series, which is actually a full-size round-shoulder dreadnought, like the J-45, and only in 12-string version.