This 18x24 poster was hand signed by all three members of Alt-J. Those members are Joe Newman, Thom Sonny Green, and Gus Unger-Hamilton while on tour in 2023. Item will be shipped in a tube. This item has been certified authentic by JSA (Jams Spence Authentication). You can verify the JSA serial number on their site. Spenceloa.com. That number is, AJ59636. Payment must be received within three days of purchase unless otherwise specified. Thank you!