NPR-Riken Corporation, together with its subsidiaries, manufactures and sells automobile engine parts, marine engine parts, and other products in Japan and internationally. The company offers automobile products, including piston rings for motorcar, motorcycle, and other internal combustion engine use; valve seat inserts; other automobile engine parts, including composite camshafts, cylinder liners, valve lifters/valve guides/rocker bridges, and valve rocker arm and others. It also provides marine and industrial piston rings; sealing rings; and metal injection molding parts for industrial equipment, office automation equipment, leisure goods, etc. In addition, the company offers compressor parts and medical equipment parts, such as dental implants. NPR-Riken Corporation is headquartered in Tokyo, Japan.