If you are playing a Freeform game
not a scenario
the game items are released a few at a time every 3 months !
(the tank filter is not released until after the first 3 months !)
If you want to use everything ingame right from the start I suggest you download and use a "freeform unlock hack"
most sites have one...
I use the MM freeform unlock from ZA
marli ... actually it was Micandra who had the answers before
credit where credit is due