Only made in 1933-34, the Kalamazoo KG-11 "Senior" only differs from the KG-11 by adding a firestripe pickguard, as well as "Senior" printed vertically on the peghead underneath the Kalamazoo logo. For those not aware. Kalamazoo was one of the many house brands made by Gibson. This one has had a very well done X-brace conversion. Great sounding and playing guitar!!