Seventeen Five (17 5) is a slang used to refer to cocaine. 17.5 is a great deal offered by suppliers when their client is purchasing a lot of coke. This slang was first popularized in Shawty Lo's underground hit "I'm Da Man," in which he rapped "And you know I keep work
Seventeen five, same color t-shirt."
In 2017, Migos released a rap song titled "Tshirt," in which they rapped "Mama told me not to sell work (mama) — Seventeen five, — same color T-shirt (white) — Mama told me not to sell work (mama) — Seventeen five, same color T-shirt (yeah)" Migos borrowed that line from Shawty Lo. They are essentially saying that their moms told them not sell drugs (work), but they sold cocaine (17 5) in the white tshirts.