I used the online size chart and my son was well within the measurements for a youth helmet, but when received it did not fit him at all. I decided to call customer service and got a recording saying they couldn't use phones because of COVID. Wow! I didn't realize it was that contagious! I left a message in July and was never called back. I continued to call and leave MANY messages over the last two months and send MANY emails. I have still not gotten a response! Terrible customer service!