Original 1st printing 13&3/4 x 21" concert poster for ex-Lovin' Spoonful leader John Sebastian appearing with Poco on 4/12/1970 and Frank Zappa (and the Hot Rats) appearing with Boz Scaggs on 4/19/1970, both shows promoted by Bill Graham Presents and held at the Berkeley Community Theatre in Berkeley, CA.
 
Artist unknown.
 
The poster is in excellent vintage condition.  It has some ligh edgewear and corner wear.  Otherwise nice.