I bought and sent the 2 pack to my Aunt . Mine was a single . I got a great crop . I think I did not let it rest long enough before trying to grow my 2nd crop . Got this very pretty white mold on my sub-strait, sent in a pic was told to err to caution ,threw it out . was told they would send me another one in the mail . Aprox 4 days it's here. Customer service is a 10+ Can't wait two dig into some more mushrooms, sausage, and onions , told a friend and while I was showing her your web site on my phone she was placing her order. love the product, the staff on the help line. and the service !!!!! Keep up the good work. ( If you ever go out of business please send me the mix recipe so I can grow my own) hope that never happens . Till then I'll order more or buy when I see them. Joel Stokes