This Autographed Spalding Zi/O Indoor / Outdoor Basketball has been Personally Signed by Nate Thurmond & Rick Barry of the Golden State Warriors. This item is 100% Authentic and comes with a PSA/DNA Certification Card and a matching numbered Hologram. This is a PSA in the Presence Authenticated item which means a PSA representative was present when this item was being signed. The authenticity can be verified on Professional Sports Authenticator website.