A sports jacket commonly worn by American high school/college students and athletes. Traditionally, the wearing of such a jacket indicates that the student has met a specified level of participation or performance on a varsity team.
Letterman jackets commonly have a large letter (hence "letter"man) on one side on the jackets chest, indicating typically the name of a school or team. The sleeves are often a different color from the jackets body. The jackets collar is often also horizontally striped.
Examples
Letterman jacket with collar stripe, different arm and body colors and letter on the chest
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