The "ECA stack" is typically purchased as three separate products (Ephedrine, caffeine, and aspirin). Ephedrine can be acquired by purchasing Bronkaid, Primatene, etc. (any product containing Ephedrine Sulfate or Ephedrine HCl). Caffeine is also easily found in 200mg pills (NoDoz is a brand name). For the aspirin, 81mg "baby" aspirin is generally used. As per the dosage, I don't really have much knowledge of that so someone else can explain it.