I want to start capping my own amino acids and electrolytes. Save me some money I was on 1fast400 and I saw their cappings machines.

Cap Em Quick (for 0)
and
Cap Em Quick (for 00)

What do the zeros mean? Also, I want some empty caps. I'll be capping 5g of taurine at most and 500mg of potassium at most. Whats a good cap size?