"I bought this costume for my grandson that just turned 4. He is average for his size and a little on the thin size. I purchased the Toddler 2-4 and he wears a 4T. It worked for his size, and I know the next size would have been too large. However, the length was a little short for a 4 and I think there should be an in-between sizing available. He simply LOVES the cape and yellow stretch belt. I wish the pants and shirt were 2 pieces vs. one. He was not real comfortable with the muscle STIFFNESS. Of well, if you want to play the role I guess you must deal with a bit of discomfort."
"This belt is very cool looking, but unfortunately is way too large for a child of normal weight. Maybe links can be taken out, but I have not found a way to do so yet. My grandson ending up using the cloth belt that came with his Batman costume that was stretchy and tied on."