I have to say the costume looked super cute-I bought two of them for my 2 1/2 yr old twin boys.  I bought the USA size 2-4...my boys are about 30 LBs and it fit them perfectly.  I would say there is a little more room for a larger child.  Looked nice on, did not look cheap at all.  The material is thin...we live in FL so that's not a problem but definitely would be in colder or snowy state and no real room for under clothes like long-johns.  Quality was better than I expected for the price.  Only have one complaint and that is that the mask was too tight and the eye holes weren't very big.  I was able to cut bigger holes so my boys wore the masks most of the night...but definitely a little tight and not too comfortable.  I would recommend this costume overall great value!