One of these on the keychain, but it only has the blade, no file on it. Goes everywhere, thru multiple ER and courthouse scanners. Never been caught. Really just used for shipping packages, zip ties, and opening kids toys.
When something more is needed a 3 blade Uncle Henry or any of an assortment of misc locking blades picked up over the years.

I have something very similar. It does just about everything I ever need it to do (mostly just opening boxes). It's not very sharp at all any more, but that's fine for my purposes.