Original 5&1/4 x 7&1/2" concert postcard for The Paul Butterfield Blues Band, Mike Bloomfield, and Birth, at the Fillmore Auditorium in San Francisco, CA on 3/27-30/1969.
 
Art by Greg Irons. image is #166 in the Bill Graham/Fillmore series. 
 
The card is in excellent condition.  The front and back are very clean.  It has a schedule back.