What's the difference between 24 Months and 2T?
Usually, months signals that the item of clothing was designed specifically for diapers—think onesies with snaps, pants with a bit more fabric on the bottom to accommodate for diapers.
2T bottoms will generally be a bit tighter and more fitted to wear over underwear.
Mostly though, these two sizes are similar
In East Asia, where our manufacturers are located, clothing sizes go by centimetres. If you see 80, 90, 100cm on our clothing, those correspond directly with 6-12M, 2T, and 3T sizing.