Do you mean Formula? If your baby drinks a regular formula like SMA or Cow & Gate, then the US version (Simillac) is identical. Both mine switched to this without a problem whilst on holiday. Its available in powder or ready made. I took several packs of those "one feed" sachets in case they didnt like the Simillac.
If you are going to take a supply from home for 2 weeks, then I would allocate 3 large tubs of powdered formula. Its is allowed into the US without a problem (though it will weigh your cases down!!!). Alternatively, if your baby is weaning and has only 3 /4 feeds a day, then a lighter alternative (but a bit more expensive!) is to take the individual sachets.
Personally, we found the Simillac fine and I was surprised as DS was quite fussy at home when I switched brands.
If I can answer anymore "baby questions" please ask away!!
Allie
PS: Make sure you check out the Baby Centers at all the Parks. They are truly wonderful and offer EVERYTHING you need for baby (including microwave, bottle warmers, cooled water, changing mats, high chairs, spoons, bowls, wipes, spare clothes, bibs, nappies, food, formula as well as TVs to keep older siblings and husbands amused!!).