child's ID tag; lost child tag
A tag attached to a child's clothing or belongings with their name and contact information, used to help reunite them with guardians if they get lost.
Please attach an ID tag to your child's clothes for the field trip.
This lost child tag has a name and phone number written on it.
迷子 means a lost child; 迷子札 is the tag used to prevent or resolve such situations.
Compound of 迷子 (maigo, 'lost child') and 札 (fuda, 'tag, label').