Hitachi Astemo Co.,Ltd. - Saitama No.1 Plant (Formerly SHOWA Corporation)

Company Profile



1-14-1, Fujiwara-cho, Gyoda, Saitama 361-8506, Japan

Business Overview

-As a company under the Honda Group, the Company operates in four segments: motorcycle & general products, automobile products, steering products, and gas-spring products. The automobile business manufactures and sells various parts for shock absorbers, propeller shafts, automatic transmissions, differential gears, power-steering systems, CVT pumps, and other products.

-In October 2019, Hitachi Ltd. and Honda announced the merger of four parts suppliers in their respective Groups, including the Company. Hitachi Automotive Systems (AMS) became the surviving company after the merger, absorbing the operations of the Company, Keihin, Nissin Kogyo that were all under the Honda Group. After the merger, Keihin will be in charge of the powertrain business. Showa will be in charge of the suspension and steering businesses. Nissin Kogyou will be in charge of the brake-systems business. AMS will engage in its areas of expertise such as powertrain systems, chassis systems, and safety systems, taking advantage of the synergy effects from Hitachi Ltd.’s advanced-digital solutions, services, and technologies, nicknamed Lumada. By doing so, the company hopes to improve the connected, safety, and mobility businesses.


-Listed on the first section of the Tokyo Stock Exchange. (As of Mar. 31, 2020)
Name and Company Name Investment Ratio (%)
Honda Motor Co., Ltd. 33.50
The Master Trust Bank of Japan, Ltd. (Trust Account) 4.13
Japan Trustee Services Bank, Ltd. (Trust Account) 2.39
Employees stockholding 1.93
Mizuho Securities Co., Ltd. 1.73
MUFG Bank, Ltd. 1.70
Total 54.17


Shock absorbers
-Showa Super Empowering Efficient Suspension
-Sensitive Frequency Response Damper
-Intelligent Electronic Control Adaptive Suspension [IECAS]

Power steerings
-Dual pinion assisted electronic power steering [DPA-EPS]
-Pinion assisted electronic power steering [PA-EPS]
-Rack assisted electronic power steering [RA-EPS]
-Hydraulic power steering [HPS]
-Power assist unit

Differential gears
-Differential carrier assemblies (floorboard suspended unit)
-Hypoid gear sets
-Pinion shafts
-Viscous couplings
-Transfer gear sets

Propeller shafts
-Single-piece propeller shafts
-Two-piece and three-piece propeller shafts

Gas springs

CVT pumps


1938 Established as Showa Koku Seiki Inc.
1946 Name changed to Showa Seisaku-sho Corp., and started to produce automobile parts.
1993 Merged with Seiki Giken Kogyo Inc., and name changed to Showa Corporation. Also started production of power steering parts.
Sep. 1995 Established Showa UK Ltd. (currently Nissin Showa UK Ltd.) in England.
Mar. 1996 Established a joint company, Sichuan Ningjiang Showa Shock Absorber Co., Ltd. in China.
Oct. 1996 Established a joint company, Nestec Inc. in Utsunomiya city, Tochigi Prefecture.
Dec. 1996 Established a joint company, Mashino- Autoparts Co., Ltd. In Vietnam.
Jan. 1997 Established American Marine Components Inc. in the USA.
Jan. 1998 Established Showa Canada, Inc. in Canada (currently a consolidated subsidiary).
Feb. 2002 Established Shanghai Showa Autoparts Co., Ltd. in China (currently a consolidated subsidiary).
June 2006 Established Showa Autoparts (Thailand) Co., Ltd., in Thailand, which is now a consolidated subsidiary.
Oct. 2006 Established Showa India Private Ltd., in India, which is now a consolidated subsidiary.
June 2007 Constructed its Saitama Plant No.2.
Apr. 2009 Constructed a new plant at its Gotemba facility. (The new plant was named Gotemba No.1 Plant, while the existing plant was renamed Gotemba No. 2 Plant.)
May. 2011 Acquired more shares of Machino Auto-Parts Co,Ltd. (currently Showa Auto-parts Vietnam Co., Ltd.) and made it a consolidated subsidiary.
Aug. 2012 Established PT. Showa Autoparts Indonesia.
Mar. 2013 Established Showa Autoparts Mexico, S.A. de C.V.
Jul. 2013 Established Showa Autoparts Wuhan Co., Ltd. in China.
Sep. 2014 Established Showa (Guangzhou) Auto parts R&D Co., Ltd.
Mar. 2018 Established Showa Deutschland GmbH.
Oct. 2019 Signed an M&A agreement that included six companies (the Company, Hitachi Automotive Systems, Keihin, Nissin Kogyo, Honda, and Hitachi Ltd.) in regard to the merger of the Company, Hitachi Automotive Systems, Keihin, and Nissin Kogyo into one company.

Supplemental Information 1