Reira,
The similac infant formula sample from hospital is not 30 ml but 120 ml.
Full bottle is 120ml, so their indicator is the other way, from full bottle, if u pour 30 ml out, the indicator balance milk as per marking is 30ml, mean balance in the bottle is 90 ml.
U can see the bottle, from top 30 ml, then 60 ml then 90 ml…..