The postcard was printed once before the concert on stock that varies in pattern and texture throughout the run. It measures 5" x 7", and its border matches the lighter pink of the 1st printing poster.
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.