- Okudaya Giken Co.,Ltd. (ORIGINAL OPK BRAND)
- Address:No. 285 Tanjo, Mihara-ku Osaka, Japan
- SUZUKI SEIKYO CO., LTD.
- Address:763, Wagocho, Naka-ku
- KONDOTEC INC.
- Address:2-90 Sakaigawa 2-Chome, Nishi-ku, Osaka, Japan
- IWATA SAW MFG CO LTD
- Address:1262 Toyohama-nakano,
- Maeda Metal Industries, ltd.
- Address:3-14-3, Fukaekita, Higashinari
- eight tool co., ltd.
- Address:9-43, 4-chome tatsumi-minami ikuno-ku Osaka Japan
- JEFCOM CO LTD
- Address:3-13-16, Nakaishikiri-cho
- GODHAND CO., LTD.
- Address:1535-5, Yoshidashimonakano
- DIATOP CORPORATION
- Address:809-1, Mukaikodara, Shirotori-cho,
- Miki Valve Engineering Co.,Ltd
- Address:6-23-1 chome nishi-ku shinmachi osaka osaka 5500013 Japan
- SUEKAGE SANGYO CO., LTD.
- Address:1-15-26, Suehiro
- TASAKI YOZAI SHOUJI CORPORATION
- Address:18-2, Azawakamiya
- Kabasawa Industry Co, Ltd
- Address:230 Hon Yoita, Yoita Town, Nagaoka, Niigata 940-2403 Japan.
- bio totto Co.,ltd
- Address:1
- Kaito Co., Ltd.
- Address:4-4-8 Sasage Konan-ku
- HIDA DENKI CO.,LTD.
- Address:282, Gokashotsukamotocho,
- MARUKOSHI KOGU CO., LTD
- Address:2-49-13, Hiratsuka
- TKB CORPORATION
- Address:Yotsubashi-Nissei Bldg. , Kitahorie,
- SGS Tool Company Asia
- Address:Yonan 4-6-47 Flower Yonan #401 Utsunomiya-shi Tochigi-ken 320-0834 Japan
- VESSEL CO.,INC.
- Address:2-17-25, Fukaekita, Higashinari-ku