If you have a true Medic Alert bracelet (from Medic Alert company), they should be replacing that emblem if it is hard to read - at least that’s what they told me once.  My daughter has worn one of their bracelets since she was diagnosed 12 yrs ago.  She has taken it off occasionally to play a sport when I am there, but it goes right back on.  She is never without it.  I agree with Paul - it is a great way to insure that in an emergency someone knows about your CAH.