Four Corner Hustler (4CH) is a People Nation gang which originated from Chicago, Illinois. Rivals of the gang say "Die 4" to inform others that they are enemies of the Four Corner Hustlers. This slang is similar to Die 5 and Die 6. Gang members who are Die 4, often crack 4s for their enemy.
One of the 4 Corner Hustler's hand signs is the 4, which they form by throwing up 4 fingers. 4CH enemies bend/crack the 4 as a sign of disrespect toward 4CH members.