Exhibit 21.1

							Jurisdiction of Incorporation
Altra Industrial Motion Corp.							Delaware
	Ameridrives International LLC						Delaware
	Boston Gear LLC						Delaware
		Bauer Gear Motor LLC					Delaware
	Formsprag LLC						Delaware
	Guardian Couplings LLC						Delaware
	Inertia Dynamics LLC						Delaware
	Kilian Manufacturing Corporation						Delaware
		Kilian Canada ULC					Canada
	Nook Industries, LLC						Nevada
	Nuttall Gear LLC						Delaware
	Stevens Holding Company Inc.						Delaware
		AS Motion LLC					Delaware
			AS Motion International B.V.				Netherlands
				AS Motion Hong Kong Ltd.			Hong Kong
				Elsim Elektroteknik Sistemler Sanayi ve Ticaret A.Ş.			Turkey
			AS Motion North America Inc.				Delaware
				American Precision Industries, Inc.			Delaware
					API Harowe (St. Kitts) Ltd.		St. Kitts and Nevis
					Heat Transfer Guarantee Co., LLC		Delaware
					Portescap S.A.		Switzerland
						Portescap Co., Ltd.	Japan
					Portescap U.S., Inc.		New York
				Ball Screws and Actuators Co., Inc.			California
				G&L Motion Control Inc.			Delaware
				Motion Engineering Incorporated			California
				Thomson Industries, Inc.			New York
					ABEK LLC		Delaware
					Thomson Industries S. de R.L. de C.V.		Mexico
				Thomson Linear LLC			Delaware
				Wermex Corporation			Texas
			PacSci Motion Control, Inc.				Massachusetts
				Kollmorgen Corporation			New York
		AT Business Systems LLC					Delaware
	Svendborg Brakes USA, LLC						Delaware
	TB Wood’s Corporation						Delaware
		TB Wood’s Incorporated					Pennsylvania
			T.B. Wood’s Canada Ltd.				Canada
			Industrial Blaju, S.A. de C.V.				Mexico
	Warner Electric LLC						Delaware
	Warner Electric Technology LLC						Delaware
	Altra Industrial Motion (Thailand) Ltd.						Thailand
	Altra Industrial Motion International Holding, LLC						Delaware
	Altra Industrial Motion Netherlands B.V.						Netherlands
		Altra Industrial Motion Denmark ApS					Denmark
			S.B. Patent Holding ApS				Denmark
			Svendborg Brakes ApS				Denmark
				Svendborg Brakes Chile Ltd.			Chile
				Svendborg Brakes España S.A.			Spain
				Svendborg Brakes India Ltd.			India
				Svendborg Brakes Korea Co. Ltd.			Republic of Korea
				Svendborg Brakes Peru S.A.C.			Peru
				Svendborg Brakes Shanghai Co., Ltd.			China
				Svendborg Brakes Trading (Shanghai) Co., Ltd.			China
		Altra Industrial Motion do Brasil Equipamentos Industriais Ltda.					Brazil
		Altra Industrial Motion Germany GmbH					Germany
			Kollmorgen Automation AB				Sweden

		Tollo Linear AB		Sweden
	Kollmorgen Europe GmbH			Germany
	Kollmorgen s.r.o.			Czech Republic
		Jacobs Vehicle Systems Europe s.r.o.		Czech Republic
		Kollmorgen S.r.l.		Italy
	Stieber GmbH			Germany
	Stromag Holding GmbH			Germany
		Stromag GmbH		Germany
			Altra Industrial Motion India Private Ltd.	India
			Stromag Dessau GmbH	Germany
	Thomson Neff Industries GmbH			Germany
Altra Industrial Motion Russia OOO				Russia
Altra Industrial Motion UK Holding Ltd.				United Kingdom
	Altra Industrial Motion UK Ltd.			United Kingdom
		Bauer Gear Motor Ltd.		United Kingdom
		Bibby Transmissions Ltd.		United Kingdom
			Altra Industrial Motion South Africa (Pty.) Ltd.	South Africa
		Huco Engineering Industries Ltd.		United Kingdom
		Matrix International Ltd.		United Kingdom
			Matrix International GmbH	Germany
		Twiflex Ltd.		United Kingdom
	AS Motion Asiapac Holding Ltd.			Hong Kong
		A&S Industry Technology (Tianjin) Co., Ltd.		China
		Portescap Singapore Pte.		Singapore
			Portescap India Private Limited	India
Bauer Gear Motor Finland Oy Ab				Finland
Bauer Gear Motor GmbH				Germany
	Aluminium Die Casting S.r.l.			Italy
	Bauer Gear Motor Europe GmbH			Germany
	Bauer Gear Motor Slovakia s.r.o.			Slovakia
Warner Electric (Holding) SAS				France
	Stromag Holding SAS			France
		Stromag France SAS		France
	Warner Electric Europe SAS			France
Warner Electric (Neth) Holding B.V.				Netherlands
	Altra Industrial Motion Australia Pty. Ltd.			Australia
	Altra Industrial Motion Hong Kong Limited			Hong Kong
		Altra Industrial Motion (ShenZhen) Co.		China
	Altra Industrial Motion Singapore Pt. Ltd.			Singapore
	Altra Industrial Motion Switzerland Sàrl			Switzerland
	Altra Industrial Motion Taiwan Ltd.			Taiwan