Packet includes Koji mold spores to make malted rice, and makes to 22 liters of Sake, with alcohol of 14-18%. Additional ingredients required are 4.2 lbs of medium grain rice, wine yeast and 5 gms citric acid.
The koji seeds are dry and extremely stable and are stored in an air lock bag. They have an indefinite shelf life being dried conidia, they need no refrigeration, and the packet can be opened and closed frequently without harm done to the contents.
For detailed instructions with photos, check out this tutorial.