Original 1st printing 14 & 1/4 x 22 & 1/2" concert poster for a benefit for Soledad Prisoner Defense and Committee for the Traditional Indian featuring the Youngbloods, Jeffrey Cain, Grootna, and Commander Cody at Friends and Relations Hall (the Old Family Dog,) in San Francisco, Ca, on 5/28-29/1971.
 
Artist inknown. 
 
The poster is in excellent vintage condition.