OZZY OSBOURNE Signed Poster Skull COA HologramOzzy Osbourne signed skull poster. 23 x 36 inch Complete with numbers certificate document and hologram from Boston memorabilia. Last one in stock! All of our Certificates of Authenticity ( COA ) state the location and date of where the autograph signature was obtained. We are the only dealer as far as we know that provides this information with every item! In the hobby of memorabilia, this is very important.