New Millennium Building Systems S-4 Registration of securities issued in business combination transactions

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Exhibit 21.1

STEEL DYNAMICS, INC
LIST OF SUBSIDIARIES

	State of Incorporation or Organization	Percent of Capital Stock/Equity Units Owned by Steel Dynamics, Inc.			Names Under which Business is Conducted
Jackson Iron & Metal Company, Inc.	Michigan		100	%	OmniSource Michigan Division
Mesabi Nugget Delaware, LLC	Delaware		83	%
New Millennium Building Systems, LLC	Indiana		100	%
OmniSource, LLC (f/k/a OmniSource Corporation)	Indiana		100	%	OmniSource Media Division OmniSource (South Carolina) LLC
OmniSource Southeast, LLC	Delaware		100	%
Roanoke Electric Steel Corporation	Indiana		100	%	Steel Dynamics Roanoke—Bar Division
Steel Dynamics Columbus, LLC	Delaware		100	%
Steel Dynamics Enterprises, Inc.	Indiana		100	%
Steel Dynamics Sales North America, Inc.	Indiana		100	%
Steel of West Virginia, Inc.	Delaware		100	%
STLD Holdings, Inc.	Indiana		100	%
The Techs Industries, Inc.	Delaware		100	%	The Techs The Techs a Division of Steel Dynamics, Inc.
Vulcan Threaded Products, Inc.	Alabama		100	%	Vulcan Steel Products CLP Systems

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Exhibit 21.1

STEEL DYNAMICS, INC LIST OF SUBSIDIARIES