Levi's first introduced the Red Tab label in 1936.
The small red fabric tab was added to the right back pocket of Levi's 501 waist overalls to distinguish the brand from competitors. Other makers had begun copying Levi's distinctive arcuate stitching, so the tab gave shoppers another visible way to identify genuine Levi's clothing.
The first Red Tabs carried the word “LEVI'S” in white capital letters on one side. This vintage design is now known among collectors as the “Big E” tab. In later decades, the lettering changed; the lowercase “e” in “Levi's” is associated with garments made from 1971 onward.
The Red Tab should not be confused with the two-horse leather patch or the arcuate back-pocket stitching. Those are separate Levi's identifiers. The tab debuted on jeans in 1936 and was later used on denim jackets and many other products.