The red tab is a branding label that’s trademarked by Levi’s. Its most recognised placement of the label on the right back pocket of Levi’s jeans.
The red tab was introduced on Levi’s jeans in 1936 as means of identifying authentic garments. It stood out vividly from the dark blue denim and instantly became synonymous with the Levi’s brand.
At that time, Levi’s hadn’t yet trademarked their arcuate, which meant competitors’ jeans also featured more or less identical back pocket signatures on their jeans.
Until 1971, the red tabs had ‘LEVI’S’ written in all capital letters, but with the introduction of the Levi’s Batwing logo in 1967, the spelling was changed to ‘Levi’s.’
This was the end of an era but the beginning the vintage ‘Big E’ craze.