My mothers Korean and shes worn slippers at home her entire life. larger size fits. My earphones are like new-almost block all noise in my studio/shop. you name it, they have never left a red mark or irritation whatsoever. Overall this is a really nice thing to have and would recommend purchasing this adapter. When its open its great, its just when your putting away or getting to it. I bought uv beads and put them in with my stuff. Not really worth the price. I have a very wide foot so I stay away from anything with a pointy toe. Third or fourth pair of Birkenstocks Ive had and they seem to be as well made as ever.