First of all thank you for your answer. I have been investigating for a while until I have found a similar product in the EEUU. As you can see, there are different companies doing the same in different countries, the globalization !!! This is the product in the EEUU: http://store.backtotheroots.com/MushroomKit_p/mushroom-kit.htm This is the one in Germany: http://www.frischepilze.com/Home-Growing-Kits--Home-Growing-Kit-Oyster-mushrooms---original-gift-idea/a42269492_u9311_z2cb6781b-d16f-4519-af93-b02b3aa2ed61/#.UihCF8b0G5Q Have you Americans heard about this mushrooms? Thank you again !!