Rounds (ARB)

Thickness: 3/8 to 4

Flats (AFL)

Thickness: 1/8 thru 1/2

Width: 3/4 thru 6

Angles (AAN)

Thickness: 1/8 thru 3/8

Legs: Equal and Unequal, 3/4 thru 4

Square Tube (AST)

Thickness: 1/8, 3/16, 1/4

Width: 1 thru 4

Channel (ACH)

Thickness: 3/16, ¼, 9/32

Various Dimensions

Pipe (API)

Thickness: S40 & S80

Diameter: ½ thru 4