From the early 1900s to the 1950s professional boxing had eight weight divisions. Two new divisions—junior lightweight and junior welterweight—were added to the original eight in the 1920s.
The poundage listed below indicates the maximum limit for each division:
Flyweight: 112 pounds
Bantamweight: 118 pounds
Featherweight: 126 pounds
Junior Lightweight: 130 pounds (1924–1939)
Lightweight: 135 pounds
Junior Welterweight: 140 pounds (1925–1942)
Welterweight: 147 pounds
Middleweight: 160 pounds
Light heavyweight: 175 pounds
Heavyweight: Unlimited