Original 1st printing 14x21 & 1/4" concert postr for The Jeff Beck Group, Spirit, Linda Tillery, Sweet Linda Devine and Sweetwater at the Fillmore Auditorium in California on 12/5-8/1968. 
 
Art by Lee Conklin, image is #148 in the Bill Graham/Fillmore series. 
 
The poster is in near mint condition.