This item is a Magic the Gathering playmat, from the Grand Prix Seattle-Tacoma 2015, featuring the Delver of Secrets artwork by Nils Hamm originally featured in Innistrad.
The playmat is unique in the fact that is double-sided, with each side featuring different artwork just like the original card did.
This item is of considerable rarity since it was never sold outside of the event.
The playmat size is around 35cm x 60cm.