The Gibson B series was a series of acoustic guitars manufactured by Gibson Guitar Corporation between 1961 and 1979, and as a reissue to a limited degree from 1991 to 1992. The series consisted of the three different models, the B-45, the B-25, and the B-15 (the Blue Book also lists a B-20, with a run of 500 units). The B-45 was only available as a 12-string edition; the B-25 was available as a standard edition, a 12-string edition, and a ¾ scale body edition; and the B-15 was only available as a standard edition.