Original 1st printing 14&1/4 x 19&7/8" concert poster for the one and only Captain Beefheart (and His Magic Band) appearing with the Charlatans at the Avalon Ballroom in San Francisco, CA from 8/26-27/1966.
 
 Art by Stanley Mouse and Alton Kelley, image is # 23 in the Family Dog/Avalon series.
 
 Medium-thick flat vellum stock poster is in good/decent (B to B/B-) condition; there are staple/pin holes in all four corners, along with a few stray handling creases/bends scattered around the outer margin area, a series of tiny pin-prick spots in the corners (bleed-through from a quartet of large glue stains on the reverse), a tiny stress crease or two hiding within the image area and a touch of light edge toning, otherwise fine- the image area looks pretty good, most of the issues are confined to the outer margin area/reverse.

Overall, a very presentable example of this fairly early Avalon poster with a classic Mouse/Kelley design.