April 1978

OKUMOTO Matsuhiro established Chugoku Seira Co., Ltd. with a capital of 5 million yen in Iida, Hachihonmatsu-cho, Higashihiroshima-shi, and started the production of nuts.

January 1983

Second Plant opened in Zoka, Takaya-cho, Higashihiroshima-shi.

January 1985

Head Office relocated to Sasa, Hachihonmatsu-cho, Higashihiroshima-shi.

April 1985

Capital increased to 20 million yen.

October 1988

Kouchi Plant opened in Kouchi-cho, Kamo-gun, Hiroshima-ken.

February 1990

Second Plant closed, and integrated with Kouchi Plant.

February 1993

Acquired manufacturing rights for locking nuts (D-Lock nuts) from Disk Lock International in the United States.

May 1996

Summit Chugoku Seira Co., Ltd. established in Bangkok, Thailand, with a capital of 20 million Baht in a joint venture with CAPCO of the Summit Group.

November 1999

ISO9002 and QS-9000 certification acquired.

January 2001

Operations integrated at current location (Hachihonmatsu Iida, Higashihiroshima-shi).

April 2001

OKUMOTO Matsuki appointed company president.

February 2006

ISO/TS 16949:2002 certification acquired.

October 2009

ISO/TS 16949:2009 certification acquired.

June 2011

Joint venture “BSG Metal Corpration Co.,Ltd.” established by “BOLTUN CORPORATION” and “Summit Chugoku Seira Co., Ltd.” in Guangzhou, China with a capital of US $1 million.

July 2013

Affiliated subsidiary “C.S. (Thailand)” established in Chonburi Province, Thailand with a capital of 10 million Baht.

March 2014

Selected as one of “Vibrant GANBARU Small and Medium Enterprises 300” (METI).

March 2015

Joined the “Iku-Boss Alliance in Hiroshima”.

August 2017

Certified as a “2017 Certified Health & Productivity Management Outstanding Organizations (Small and Medium Enterprise Category)” (METI).

September 2017

Increased capital for affiliated subsidiary C.S. (Thailand) to 30 million Baht.

November 2017

IATF 16949:2016 certification acquired.