There are two variations of the original, pre-concert printing of the postcard.
1st printing A is on thin coated glossy stock, reflecting a bright blue background. It measures 5" x 7".
1st printing B is on plain, dull thicker stock, which reveals a drab blue background. It also measures 5" x 7".
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.