One out of 10 red Tabs on the back pocket of a pair of Levi’s® jeans is a blank red Tab and does not include the name Levi’s®. Check your red Tab and see if your pair is one of them.
The red Tab was added to Levi’s® jeans in 1936 because competitors were mimicking several features, especially the Arcuate, the signature stitching on the back pockets.
以上內容轉載自，這裡Levi's的FB官方粉絲團，
單R標並不是千分之一或百分之一和萬分之一喔，
他出現的機會是十分之一的機率，
裡面開頭就說One out of 10，意思就是10件出1件，
並不是什麼特別稀有的東西!
我前幾天剛好也買到一件單R標，所以才特別去找它的資訊
