The 1st printing posters are of varying quality; some are sharp and others muddy because of printing problems in the original run. The irregularities consist mostly of red ink smearing and extending outside the black border, into the lettering or bull image. The poster is 14 3/16" x 20" and was printed on vellum before the concert.

The post-concert 2nd printing is 14 3/8" x 20" on white index and shows "No.13-2" in the lower right corner and the Washington Street address in the lower left corner.

Born in Detroit, Stanley Miller became known as "Mouse" after illustrating countless notebooks with his signature rodent sketch. Miller found an outlet for his creativity in pin-striping cars and airbrushing hot rod designs on posters and T-shirts. Mouse migrated to San Francisco in 1964, where he first met the artists associated with Family Dog, the organization producing dance concerts at the Avalon Ballroom. With collaborator Alton Kelley, Mouse experimented broadly with composition, lettering and imagery: Kelley came up with the ideas and Mouse executed the designs. Mouse and Kelley helped to establish the psychedelic style of expression under the name Mouse Studios.