I only tried it on indoors because it was already small when I received it, so it's almost unused. The plastic film is still attached to the back of the sunglasses part. It's authentic. Please see the tag. It's a kids' size S. When laid flat, the part that covers the head is about 17cm long. It's sold for 15,900 yen on Farfetch. I plan to put it in a Yu-Packet Post cardboard box and drop it off at the post office.