Nearly all U.S. material, I have something for everyone from classics to current day stamps, booklets, blocks, Zip and plate blocks,full panes, and mint sheets mint and used. I have been selling on the internet since about 1995 and have a 99.96% feedback score. I am constantly adding items to replenish my inventory so please continue to "check in". Generally all store items will allow reasonable "best offers" if they don't, please email me so I can edit the listing to allow them.