Staff T-shirt gallery
Staff T-shirt 2010 version
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The so-called "flame pattern" seems to have been somewhat popular at the time. It is also called a fire pattern.
It was designed by a person who really wanted to use the flame pattern, based on his personal taste.
When I was standing in the store wearing this, an elementary school boy who was visiting with his father
“So cool!”
I have fond memories of being told that (lol)