EXHIBIT 21.1

SUBSIDIARIES OF THE REGISTRANT

Name of Corporation	Jurisdiction Of Incorporation or Organization	% of Voting Securities Held at December 31, 2011 (1)
Amcorp, Inc.	Delaware		100	%
ASC Holdings, Inc.	Utah		100	%
Amaltex, Inc.	Texas		100	%
Andrews County Holdings, Inc.	Delaware		100	%
Waste Control Specialists LLC	Delaware		100	%
Kronos Worldwide, Inc. (2)	Delaware		50	%
NL Industries, Inc. (2), (3), (4)	New Jersey		83	%
CompX International Inc. (4)	Delaware		87	%
Tremont LLC	Delaware		100	%
TRECO L.L.C.	Nevada		100	%
Basic Management, Inc.	Nevada		32	%
Basic Water Company	Nevada		100	%
Basic Environmental Control LLC	Nevada		100	%
Basic Power Company	Nevada		100	%
Basic Remediation Company LLC	Nevada		100	%
Basic Land Company	Nevada		100	%
The Landwell Company LP	Delaware		50	%
The Landwell Company LP	Delaware		12	%
TRE Holding Corporation	Delaware		100	%
TRE Management Company	Delaware		100	%
Tall Pines Insurance Company	Vermont		100	%
Medite Corporation	Delaware		100	%
Impex Realty Holding, Inc.	Delaware		100	%

(1) Held by the Registrant or the indicated subsidiary of the Registrant.

(2) Subsidiaries of Kronos are incorporated by reference to Exhibit 21.1 of Kronos’ Annual Report on Form 10-K for the year ended December 31, 2011 (File No. 333-100047). NL owns an additional 30% of Kronos directly.

(3) Subsidiaries of NL are incorporated by reference to Exhibit 21.1 of NL’s Annual Report on Form 10-K for the year ended December 31, 2011 (File No. 1-640).

(4) Subsidiaries of CompX are incorporated by reference to Exhibit 21.1 of CompX’s Annual Report on Form 10-K for the year ended December 31, 2011 (File No. 1-13905).