The 1st printing poster presents a darker red and green than the 2nd printing. The most distinguishing feature is the presence of a black dot at about 2 o'clock on the "O" after the "L" in Youngbloods at the top of the poster. It was printed before the concert and measures 14" x 20".
The post-concert 2nd printing shows lighter colors than the original and omits the black dot in the "O" of the 1st printing. There are also some faint vertical bars that extend from the green border where it curves left at the top that are not present in the 1st printing. It also measures 14" x 20".
Born in Spain, Victor Moscoso was the first of the rock poster artists with serious academic training and experience. At the Avalon Ballroom in San Francisco, Moscoso saw rock posters and decided that he could "make some money doing posters for those guys." In 1966, he began designing posters for the Avalon Ballroom; and under his own imprint, Neon Rose, a series for the Matrix, a San Francisco nightclub. Moscoso's style is most notable for its visual intensity, which was obtained by manipulating form and color to create optical effects. He used clashing, vibrating colors and deliberately illegible psychedelic lettering to demand attention.