Original 1st printing 14&1/8 x 20" concert poster for Chicago blues legend Howlin' Wolf appearing with Big Brother & the Holding Company (featuring Janis Joplin) at the Avalon Ballroom in San Francisco, CA from 9/23-24/1966 (*show was canceled). 
 
 Art by Stanley Mouse and Alton Kelley, image is # 27 in the Family Dog/Avalon series. (OP-2 in the Eric King guide, the version with the darker red/orange-border lettering)
 
 Medium-thick flat vellum stock poster is in very good to excellent (B/B+ to B+) condition; this example has a thin sliver of toning around the outer margin area (matte burn), along with a set of TINY pin holes (all four corners), a bit of mild crinkle creasing along the extreme lower right margin, a bit of pin-prick spotting along the lower left margin, a few soft handling dings and a stray pin-prick spot or two hiding within the image area and a tiny pressure crease along the upper right margin, otherwise fine.

VERY nice-looking gently-worn example of this ICONIC mid-'66 Mouse/Kelley poster from the Avalon.