Original 1st printing 8&1/2 x 11" double-sided (mailer reverse) concert flyer for Country Joe & the Fish appearing with Lee Michaels and Moby Grape at the Avalon Ballroom in San Francisco, CA from 12/30-31/1966.
 
 Art by Stanley Mouse and Alton Kelley, image is # 41 in the Family Dog/Avalon series. This version is known as OHB-B in the Eric King guide.
 
 Thin flat stock flyer is in near mint (A-) condition; essentially mint, but there may be one or two nearly-invisible pinch dings/edge bends, so for argument's sake I will say it's just a hair beneath PERFECT (if there even is such a thing). GORGEOUS example of this hard-to-find Avalon flyer (last monochrome thin-paper flyer in the series).