TheRealVan

Hey, this is probably just my stupidity, but the 5m parts don't seem to appear in the tech tree when I try to unlock them. They are apparently available in the VAB just greyed out and says "This part needs to be unlocked in R&D" or something along those lines. Parts in question are the 5m SAS ring halves and the 5m adapter tanks. Anyone else with this problem? Could someone tell me where these should be in the tech tree if I'm just being blind? Thanks!