Exhibit 21.1

Subsidiary	Registered in	Acquired
A. M. Castle & Co. (Canada) Inc.	Ontario	July 31, 1990
Advanced Fabricating Technology LLC.	Delaware	May 1, 2000
Castle Metals de Mexico S.A. de C.V.	Mexico	February 27, 2004
A. M. Castle & Co. (Singapore) Pte. Ltd.	Singapore	October 13, 2006
Keystone Tube Company	Delaware	June 2, 1997
Metal Express	Delaware	September 17, 1997
Oliver Steel Company	Delaware	July 15, 1998
Paramont Machine Company, LLC	Delaware	April 1, 1999
Total Plastics, Inc.	Michigan	January 2, 1996
Transtar Intermediate Holdings #2, Inc.	Delaware	September 5, 2006
Transtar Metals Holdings	Delaware	September 5, 2006
Transtar Inventory Corp.	Delaware	September 5, 2006
Transtar Metals Corp.	Delaware	September 5, 2006
Transtar Marine Corp.	Delaware	September 5, 2006
A.M. Castle Metal materials (Shanghai) Co., Ltd.	Pu Dong Province, Peoples Republic of China	November 22, 2007

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