EXHIBIT 21.1 SUBSIDIARIES OF THE COMPANY National-Oilwell, L.P. Delaware NOW International, Inc. Delaware National-Oilwell Canada Ltd. Canada TS&M Technical Sales & Maintenance Ltd. Canada National Oilwell (U.K.) Limited UK Hitec Drilling & Marine Systems, Ltd. UK National Oilwell de Venezuela C.A. Venezuela National-Oilwell Pte. Ltd. Singapore National-Oilwell Pty. Ltd. Australia Russell Sub-Surface Systems, Ltd. UK National Oilwell - Netherlands B.V. Holland NOW International Denmark ApS Denmark P.T. National Oilwell Indonesia Indonesia Dreco Energy Services, Ltd. Canada Dreco DHT, Inc. Delaware Vector Oil Tool Ltd. Canada Hitec Systems and Controls, Inc. Canada Dreco International Holdings, Ltd. Canada Dreco Limited (UK) UK National Oilwell DHT, L.P. Delaware National Oilwell Norway Holdings AS Norway National Oilwell Norway AS Norway Hitec AS Norway Maritime Industry Services AS Norway National Oilwell-Hydralift AS Norway Hydralift ASA Norway Hydralift Holding, Inc. Delaware Hydralift-AmClyde, Inc. Delaware Hydralift, Inc. Delaware Hydraift France SAS France Hydralift BLM SA France Hydralift Holding (UK) Ltd. UK