Mr Walker Alias
The Phantom's birthname is Christopher Walker (Kit and Chris are shorthand names for Christopher). Naturally then, this is his "undercover" alias. In order to preserve the mystery and legend around The Phantom, when not in the jungle or on a task as The Phantom, he dresses as Mr Walker.
The Old Jungle Saying is "There are times when the Phantom leaves the jungle and walks the streets of the town like an ordinary man."
Exact clothing should be period and situation appropriate, but whatever the garb the eyes should remain hidden (with dark glasses or a hood / hat). The costume is generally worn underneath.
The 21st Phantom "Mr Walker" Costume
The 21st Phantom "Mr Walker" alias costume for most of the first 80 years was a long trench coat, often with a scarf, and a fedora style hat. Recently the trench coat has been replaced with a more modern looking bomber jacket.
Both are acceptable with the trench coat still in use by many creators. The modern newspaper stories feature the bomber jacket and is more practical, or increasingly even a wide range of "ordinary man" attire.
In some stories he will wear non 'Walker attire' when needed. If this happens, his face, eyes and identity are always covered.
Examples of Past Phantom's "Mr Walker" Costume
As you will see, past Phantom's "ordinary man" costume depends on the environment and time period he is in. You will see him dress with a simple cloak, an Arabian outfit, renaissance fashion, American western, and many more.
When The Phantom is Not on Mission
When the Phantom is not on mission, he wears the Skull Ring on the inside of his fingers so on the outside it looks like a simple wedding ring.
This has only been shown in one Lee Falk story, it is accepted lore to many phans. We would suggest it be used more.
This example is from the "The Masked Ball" written by Lee Falk and drawn by Sy Barry.
The Phantom Suit out of context
The Phantom in full hero costume should not be presented where it would be out of context (ie, walking into a department store near Leicester Square, or strolling into the foyer of the United Nations Headquarters).
"The Masked Ball" (D104) is an example of creators playing with this premise though where he used the costume for the Ball.