Original  8"x5&1/2" concert postcard for Jefferson Airplane and The Grateful Dead at the Fillmore Auditorium in San Francisco, CA on 8/12-13/1966. 
 
Art by Herb Greene and Wes Wilson, image is #23 in the Bill Graham/Fillmore series. 
 
Postcard is in Near Mint/Mint (A-/A) ;  a fine-looking example of this early  postcard.