They come in a small wood block. Notched in is the strain name and history of the strain on the back. Seeds are sealed in the block in a glass vile with a wax of some sort.
Maybe you get the tin if you order a 3 pack or smaller and the block is for more than a 3 pack. I ordered a 3 pack of the chemdawg and got a small vial in a round metal tin.
I ordered a 3 pack of the lemon juice express and it too came in the wood block with its strain details carved in. If you selected the tin option then that is why it came this way. Original breeder packs will land you the wood. Hope this was helpful