Original 1st Printing 7&1/4 x 9&1/4" concert double postcard for Sons of Champlain, Siegel Schwall, Mark Almond, Commande Cody, Poco and Wishbone Ash, at the Fillmore West in San Francisco, CA on 3/11-14 and 3/18-21/1971. It is considered postcard Type C.  It has a schedule back.
 
Art by Norman Orr. image is #176 and 177 in the Bill Graham/Fillmore series. 
 
Postcard is in good condition.  There is a handling crease on the top, and edgewear and corner wear throughout. F-273-274 is written in pen on the back.