Exhibit 21.1

SUBSIDIARIES OF THE REGISTRANT

Name

State or Country of Incorporation

Acker Holdings LLC

United States

Advanced Wirecloth, S. de R.L. de C.V.

Mexico

AF Global FZE

United Arab Emirates

Ameron B.V.

Netherlands

Ameron International Corporation

United States

Ameron Singapore Holding, LLC

United States

APL Norway AS

Norway

Arabian Rig Manufacturing Company

Saudi Arabia

ASEP Otomotiv Sanayi Ticaret Ltd.

Turkey

Big Red Tubulars Limited

Virgin Islands, British

Bondstrand Ltd.

Saudi Arabia

Chemineer, Inc.

United States

Coil Services Middle East LLC

United Arab Emirates

Coöperatie Intelliserv Holding U.A.

Netherlands

Coöperatie NOV NL U.A.

Netherlands

Environmental Procedures LLC

United States

EURL NOV Oil & Gas Services Algeria

Algeria

Fiber Glass Systems (Qingdao) Composite Piping Co., Ltd.

China

Fiber Glass Systems Oman L.L.C.

Oman

Fiber Glass Systems, L.P.

United States

Fibra Ingenieria y Construccion S.A.

Chile

Fjords Processing France SAS

France

Fjords Processing Korea Co. Ltd.

Korea, Republic of

Fjords Processing Limited

United Kingdom

Fjords Processing Middle East DMCC [In liquidation]

United Arab Emirates

Fortress Downhole Tools, L.L.C.

United States

GPEX, L.P.

United States

Grant Prideco (Singapore) Pte Ltd

Singapore

Grant Prideco de Venezuela, S.A.

Venezuela, Bolivarian Republic of

Grant Prideco III C.V.

Netherlands

Grant Prideco Jersey Limited

Delaware

Grant Prideco Mauritius Limited

Mauritius

Grant Prideco Netherlands B.V.

Netherlands

Grant Prideco, Inc.

United States

Grant Prideco, S. de R.L. de C.V.

Mexico

GustoMSC B.V.

Netherlands

Hebei Huayouyiji Tuboscope Coating Co., Ltd.

China

Hellenes Limited

United Kingdom

Hydralift AmClyde, Inc.

United States

Intelliserv GP Holdings LLC

United States

Intelliserv International Holding, Ltd

Cayman Islands

IntelliServ Norway AS

Norway

Intelliserv, Inc.

United States

Intelliserv, LLC

United States

Keystone Tower Systems, Inc.

United States

KTS Texas #1, LLC

United States

Midsund Bruk AS

Norway

Mono Group Pension Trustees Limited

United Kingdom

Mono Pumps New Zealand Company

New Zealand

Moyno, Inc.

United States

National Oilwell (U.K.) Limited

United Kingdom

National Oilwell Algerie

Algeria

National Oilwell de Venezuela, C.A.

Venezuela, Bolivarian Republic of

National Oilwell Varco (Beijing) Investment Management Co. Ltd.

China

National Oilwell Varco (Thailand) Ltd.

Thailand

National Oilwell Varco Algeria

Algeria

National Oilwell Varco Almansoori Services

United Arab Emirates

National Oilwell Varco Bahrain WLL

Bahrain

National Oilwell Varco de Bolivia S.R.L.

Bolivia

National Oilwell Varco de Chile - Servicios Limitada

Chile

National Oilwell Varco Denmark I/S

Denmark

National Oilwell Varco do Brasil Ltda.

Brazil

National Oilwell Varco Egypt LLC

Egypt

National Oilwell Varco Eurasia, LLC

Russian Federation

National Oilwell Varco Guyana Inc.

Guyana

National Oilwell Varco Hungary Limited Liability Company

Hungary

National Oilwell Varco Korea Co., Ltd.

Korea, Republic of

National Oilwell Varco MSW S.A.

Argentina

National Oilwell Varco Muscat SPC

Oman

National Oilwell Varco Norway AS

Norway

National Oilwell Varco Peru S.R.L.

Peru

National Oilwell Varco Petroleum Equipment (Shanghai) Co., Ltd.

China

National Oilwell Varco Poland Sp. z o.o.

Poland

National Oilwell Varco Pte. Ltd.

Singapore

National Oilwell Varco Romania S.R.L.

Romania

National Oilwell Varco Solutions, S.A. de C.V.

Mexico

National Oilwell Varco UK Limited

United Kingdom

National Oilwell Varco Ukraine LLC

Ukraine

National Oilwell Varco, L.P.

United States

NOV - Oil Services Angola, LDA.

Angola

NOV (Asia) Inc.

Mauritius

NOV (Barbados) Holding SRL

Barbados

NOV (Barbados) SRL

Barbados

NOV (Caymans), Ltd.

Cayman Islands

NOV (Jiangsu) Energy Equipment Limited

China

NOV Africa Pty Ltd

South Africa

NOV Australia Pty Ltd

Australia

NOV Azerbaijan LLC

United States

NOV Brandt Europe France

France

NOV Brandt Oilfield Services Middle East LLC

United Arab Emirates

NOV Canada ULC

Canada

NOV CAPS Pte. Ltd.

Singapore

NOV Completion and Production Solutions Korea Ltd.

Korea, Republic of

NOV Completion Tools LLC

Russian Federation

NOV Côte D’Ivoire SARL

Ivory Coast

NOV Curaçao B.V.

Curaçao

NOV Denmark Coöperatief U.A.

Netherlands

NOV Digital Technologies Private Limited

India

NOV Doha Energy Trading and Services LLC

Qatar

NOV Doha Factory for Metal Products LLC

Qatar

NOV Downhole Eurasia Limited

United Kingdom

NOV Downhole Italia S.R.L.

Italy

NOV Downhole KZ, LLP

Kazakhstan

NOV Elmar (Middle East) Limited

United Kingdom

NOV Energy Kuwait for Maintenance of Oil Facilities, Wells, Refineries and Petrochemicals SPC

Kuwait

NOV Energy Mexico, S. de R.L. de C.V.

Mexico

NOV Equipment Manufacturing Sole Proprietorship LLC

United Arab Emirates

NOV Eurasia Holding LLC

United States

NOV Expatriate Services, Inc.

United States

NOV FGS Malaysia Sdn Bhd

Malaysia

NOV FGS Singapore (Pte.) Ltd

Singapore

NOV Flexibles Equipamentos E Servicos Ltda.

Brazil

NOV France SAS

France

NOV Gabon SARL

Gabon

NOV GEO LP1 LLC

United States

NOV GEO LP2 LLC

United States

NOV Germany GmbH

Germany

NOV Germany Holding GmbH

Germany

NOV Ghana Limited

Ghana

NOV Grant Prideco L.L.C.

United Arab Emirates

NOV Holding Danmark ApS

Denmark

NOV Holding UK 1 Limited

United Kingdom

NOV Holding UK 2 Limited

United Kingdom

NOV Holdings B.V.

Netherlands

NOV India Private Limited

India

NOV Intelliserv UK Limited

United Kingdom

NOV International Holdings LLC

United States

NOV Kenya Limited

Kenya

NOV Kostroma LLC

Russian Federation

NOV Kuwait for Repair and Maintenance of Light and Heavy Equipment – KDIPA S.P.C.

Kuwait

NOV Mexico Holding LLC

United States

NOV MFG India Private Limited

India

NOV Middle East FZE

United Arab Emirates

NOV Middle East Oil and Natural Gas Wells Equipments and Devices – L.L.C. – S.P.C.

United Arab Emirates

NOV Mozambique Limitada

Mozambique

NOV NL Mexico Holding B.V.

Netherlands

NOV Oil & Gas Services Egypt (S.A.E)

Egypt

NOV Oil & Gas Services Sénégal S.A.R.L.

Senegal

NOV Oil & Gas Services Uganda Limited

Uganda, Republic of

NOV Oil and Gas Services Ghana Limited

Ghana

NOV Oil and Gas Services Namibia (Proprietary) Limited

Namibia

NOV Oil and Gas Services Nigeria Limited

Nigeria

NOV Oil and Gas Services South Africa (Pty) Limited

South Africa

NOV Oilfield Services Tanzania Limited

Tanzania, United Republic of

NOV Oilfield Services Vostok LLC

Russian Federation

NOV Oilfield Solutions Ltd.

Nigeria

NOV Park II B.V.

Netherlands

NOV Process & Flow Technologies AS

Norway

NOV Process & Flow Technologies Malaysia Sdn. Bhd.

Malaysia

NOV Process & Flow Technologies UK Limited

United Kingdom

NOV Products Middle East FZE

United Arab Emirates

NOV QFZ LLC

Qatar

NOV Rig Solutions Pte. Ltd.

Singapore

NOV Romania, LLC

United States

NOV Saudi Arabia Co. Ltd.

Saudi Arabia

NOV Saudi Arabia Trading Co.

Saudi Arabia

NOV Services Ltd.

Cayman Islands

NOV Shared Services Mexico, S. de R.L. de C.V.

Mexico

NOV Tuboscope Italia S.R.L.

Italy

NOV Tuboscope NL B.V.

Netherlands

NOV Tubulars and Connectors Ltd.

Nigeria

NOV UK Holdings LLC

United States

NOV UK Korea LP

United Kingdom

NOV Wellbore Technologies do Brasil Equipamentos E Serviços Ltda.

Brazil

NOV Wellbore Technologies Norway LLC

United States

NOV Wellsite Services Germany GmbH

Germany

NOV Worldwide B.V.

Netherlands

NOV-BLM SAS

France

NOVM Holding LLC

United States

NOW International LLC

United States

NOW Oilfield Services, LLC

United States

NQL Holland B.V.

Netherlands

Pesaka Inspection Services SDN.BHD.

Malaysia

Pipex Limited

United Kingdom

PT Fjords Processing Indonesia

Indonesia

PT H-Tech Oilfield Equipment

Indonesia

PT Managed Pressure Operations

Indonesia

PT National Oilwell Varco

Indonesia

PT NOV Oilfield Services

Indonesia

PT Profab Indonesia

Indonesia

R&M Energy Systems de Venezuela, C.A.

Venezuela, Bolivarian Republic of

R&M Singapore Holding LLC

United States

RE.MAC.UT. S.r.l.

Italy

ReedHycalog International Holding, LLC

United States

ReedHycalog UK Limited

United Kingdom

ReedHycalog, L.P.

United States

RHI Holding LLC

United States

Robannic Overseas Finance VBA

Aruba

Robbins & Myers B.V.

Netherlands

Robbins & Myers Holdings, LLC

United States

Robbins & Myers N.V.

Curacao

Robbins & Myers, Inc.

United States

STAR Sudamtex Tubulares S.A.

Venezuela, Bolivarian Republic of

Subseaflex Holding ApS

Denmark

T-3 Energy Services Cayman Holdings, Ltd.

Cayman Islands

T-3 Energy Services Cayman, Ltd.

Cayman Islands

T-3 Energy Services, LLC

United States

Telluride Insurance Limited

Bermuda

Tianjin Grant TPCO Drilling Tools Company Limited

China

Tuboscope & Co. LLC

Oman

Tuboscope (Holding U.S.) LLC

United States

Tuboscope Brandt de Venezuela, S.A.

Venezuela, Bolivarian Republic of

Tuboscope Norge AS

Norway

Tuboscope Vetco (France) SAS

France

Tuboscope Vetco (Österreich) GmbH

Austria

Tuboscope Vetco Capital Limited

United Kingdom

Tuboscope Vetco de Argentina S.A.

Argentina

Tuboscope Vetco Moscow CJSC

Russian Federation

Tubular Coatings Solutions Ltd.

Saudi Arabia

Tucom Composites Polyester Sanayi Ticaret Ltd.

Turkey

Varco BJ B.V.

Netherlands

Varco CIS, LLC

Russian Federation

Varco International de Venezuela, C.A.

Venezuela, Bolivarian Republic of

Varco US Holdings LLC

United States

Varco, L.P.

United States

Vetco Enterprise GmbH

Switzerland

Vetco Saudi Arabia Ltd.

Saudi Arabia

Visible Assets, Inc.

United States

voestalpine Tubulars GmbH

Austria

voestalpine Tubulars GmbH & Co KG

Austria

Woolley, Inc.

United States

XL Systems Antilles, N.V.

Curacao

XL Systems Europe B.V.

Netherlands