豬耳繩 is Cantonese slang for cheap or faked jewelry. Apparently the term originated from a shop in Foshan (佛山) near Guangzhou （廣州）named 朱義盛, which specialized in jewelry made of plated gold. The name understandably became an euphemism for faked, or simply cheap jewelry. I have no idea how it degenerated into 豬耳繩.
This particular shop is in Yaumatei (油麻地). It is delicious irony that it calls itself “Honest Company”. Perhaps they are honestly selling “real” faked jewelry? Instead of “faked” faked jewelry, whatever that means?