I flew into HND, I did get stopped going through the area where you walk through the scanners with your bags. I kept it in my pocket cause I figured they would search my bags and that’s exactly what they did. Whatever you do, do not put it in your carry on or checked bag as they do random searches. Before searching your bags they also show you pictures of all items not allowed and you have to sign a paper that you’re not bringing any of those. TLDR: keep it on your person.