Original 2nd printing (1st postcard printing) 4&5/8" X 7" concert postcard for Free, Bloodrock and Edward's Hands at the Fillmore Auditorium in San Francisco, CA from 1/14-17/19671.  There is an ad backing.
 
 Art by David Singer.  Signed by David Singer.   image is # 266 in the Bill Graham/Fillmore series.
 
 Medium-thin flat index stock postcard is in mint/near mint (A/A-) it is a terrific example of this early postcard with a great design.