SKF (Svenska Kullagerfabriken) is a Swedish industrial manufacturing company founded in 1907 and headquartered in Gothenburg. Its founder, Sven Wingquist, invented the world's first self-aligning double-row ball bearing. This innovation significantly improved the stability and lifespan of mechanical operations and established SKF's leading position in the global bearing technology field.

NSK (Nippon Seiko Co., Ltd.), founded in 1916, is Japan's first professional manufacturer of bearings, headquartered in Shinagawa Ward, Tokyo. As one of the world's leading manufacturers of bearings and precision machinery, NSK's products are widely used in the automotive, industrial machinery, home appliance, railway, and aerospace industries.

GMN (Georg Müller Nürnberg) is a high-precision machinery manufacturer headquartered in Nuremberg, Germany. Founded in 1908, it has a history of over a century. The company specializes in producing high-precision ball bearings, mechanical spindles, one-way clutches, and non-contact seals, which are widely used in high-end industries such as machine tools, aerospace, medical equipment, and semiconductor manufacturing.

FAG (Fischers Aktien-Gesellschaft) is a renowned German bearing brand and a key member of the Schaeffler Group. Its history dates back to 1883, when Friedrich Fischer founded the company in Schweinfurt, Germany, and invented the first machine capable of precisely grinding steel balls, laying the foundation for the mass production of modern rolling bearings.

NTN Corporation is one of Japan's three major bearing manufacturers, alongside NSK (Nippon Seiko) and JTEKT. Headquartered in Nishi-ku, Osaka, Japan, the company specializes in the research and development and manufacturing of bearings, constant velocity joints (CVJs), and precision mechanical parts, which are widely used in the automotive, industrial machinery, aerospace, and energy sectors.

Rexnord Corporation is an industrial manufacturing company headquartered in Milwaukee, Wisconsin, USA. Founded in 1891 as the Chain Belt Company, it initially focused on producing chain drive systems as alternatives to belts. After several mergers and reorganizations, the company changed its name to Rexnord in 1973 and has since grown into a leading global provider of power transmission and water management solutions, with brands including Falk, LinkBelt, Sealmaster, Kop-Flex, Browning, McGill, and Rollway.