Filed by Minebea Co., Ltd.

Pursuant to Rule 425 under the U.S. Securities Act of 1933

Subject Company: MITSUMI ELECTRIC CO., LTD. (File Number: 132-00001)

Dated December 21, 2015

Execution of Basic Agreement towards Business Integration of Minebea and Mitsumi Excerpt) December 21, 2015 Minebea Co., Ltd. Yoshihisa Kainuma, Representative Director, President and Chief Executive Officer MITSUMI ELECTRIC CO., LTD. Shigeru Moribe President and Representative Director

Becoming the "ultimate electro mechanics solutions provider" through the Business Integration Aim to become the ultimate electro mechanics solutions provider by establishing a powerful manufacturer of ultra high-precision processing parts and communications/sensors parts through the combination of analog and digital technologies Birth of an electro mechanics solutions provider with net sales of more than 900 billion yen and operating income of more than 80 billion yen Electronic components business Machined components business Establishment of a firm foundation to becoming a one-of-a-kind, genuine full-line parts manufacturer in the world with more than 1 trillion yen in net sales and 100 billion yen in operating income The combination of Mitsumi's more than 1,000 engineers and Minebea's technologies of ultra high- precision processing/molds, mass-production technology, including advanced automation technology, and large-scale plants Large synergistic effects on management resulting from combining Minebea's speedy management with its accurate grasp of the market's needs and Mitsumi's technological seeds and strong financial foundation 1

Achieving a product portfolio that captures the needs of the IoT era Mitsumi's products include many input, conversion and control devices, such as switches, sensors and connectors, while Minebea's products comprise many output devices, such as motors and actuators. The complementary combination of the two companies that have accumulated technologies in different areas will create the best foundation for the development of innovative products. The combination of Mitsumi's input, conversion and control devices and Minebea's output devices will accelerate the expansion of OEM/ODM manufacturing business as well as the promotion of the development and supply of high value-added solutions. Force sensors and PSAs Resolvers Electrostatic switches? (Cool Leaf) Input devices MEMS sensors MEMS environment sensors Milliwave radar Batteryless switch Switches Connectors Camera modules Antennas Communication modules AC adapters Inverter circuits Conversion and control devices Battery protection IC Battery monitoring IC Power supply IC Switched-mode power supply Auto-focus actuators Optical image stabilizer (OIS) for cameras Vibration power generation devices Rods and bearings Motors Actuators Fans and blowers LED backlights Lightning equipment Moving back lights Output devices Motors MEMS mirror application products 2

The perspective from Minebea: Mitsumi's core competence further accelerates Minebea's rapid growth Due to its rapid growth, Minebea requires more human resources with more diversified professional skills in order to achieve further growth. 1 There has been an increasing need for a combination of machine processing, electronic technology and communications/sensors technology in an IoT era that aims to realize an environmentally-friendly, efficient social life. The business combination will immediately strengthen the communications/sensors technology area, the third pillar of Minebea's business, to achieve electro mechanics solutions. 2 Strategically reconstruct the business portfolio by focusing on high-end and niche markets where the two companies can succeed by reviewing the companies' business portfolio to be developed in the future, and concentrating resources in such markets. Synergies are also expected in Minebea's products currently under development. 3 Aim to achieve the target of 1 trillion yen in net sales and more than 100 billion yen in operating profit ahead of schedule by creating products that utilize the strengths of the integration, such as the efficient use of global manufacturing bases of both companies and making agile investments in low-cost manufacturing. 3

The perspective from Mitsumi: Realize Mitsumi's potential through Minebea's management resources Mitsumi's business challenge is the shortage of management resources for the expansion of existing businesses and expansion into new businesses despite the many seeds for new businesses that it has from its first-in-class product design and development capabilities. Synergies 1 Will be able to advance the business in an advantageous manner in the precision mechanics parts business in all aspects, including in performance, quality and cost, by combining Minebea's high-precision processing (molds) and automation technology with Mitsumi's product development capabilities, including simulation technology. 2 Achieving lower fixed costs through, among others, significant improvement in productivity by reallocating manufactured goods and mutually utilizing both companies' manufacturing bases and technologies as well as automation technologies. Also achieve lower variable costs by making large-scale and joint procurement of materials and parts. 3 Through cross-selling that leverages Mitsumi's sales channel, which has strength in EMS and ODM, and Minebea's sales channel, which has strength in general-purpose parts, unearth potential demand and provide new solutions to customers. 4

Synergies from the combination of Minebea and Mitsumi: Enhancement of cost competitiveness and capacity to generate cash flow by optimizing manufacturing structure and bases Mutual use of factories and optimization of manufacturing bases of Minebea and Mitsumi Semiconductor devices, mechanism parts, high-frequency parts Mechanism parts Semiconductor devices, power supply parts Electronic devices and components Machinery components, electronic devices and components Mechanism parts, high-frequency parts, power supply parts High-frequency parts Mechanism parts Mechanism parts, high-frequency parts Machinery components, electronic devices and components Electronic devices and components Power supply parts Machinery components, electronic devices and components Mitsumi Minebea Semiconductor devices High-frequency devices Optical devices, mechanism parts Mechanism parts, power supply parts, others Semiconductor devices Mechanism parts, power supply devices Machinery components, electronic devices and components Electronic devices and components Electronic devices and components, optical instruments Machinery components, electronic devices and components Semiconductor devices, mechanism parts, high-frequency parts, power supply parts Semiconductor devices, optical devices, mechanism parts Machinery components High-frequency parts 5

Accelerating entrance into new strategic business areas through synergistic effects resulting from Minebea's ultra high-precision processing technology and Mitsumi's electronics technology Target markets Medical care/nursing care Industrial Infrastructure Robotics Automobiles Information/communication Creation of new products Existing businesses Strengths Output devices Processing technology/ optical technology/ mechanism technology General-purpose products Strengths Input devices Electronics and communications technology Custom products Expansion of businesses through synergistic effects resulting from combining existing businesses 6

Synergies from the combination of Minebea and Mitsumi: Biological information monitoring system Biological information monitoring system using medical bed sensors Control modules Wireless modules High-precision load sensors Forecast of home healthcare market by biological measurement equipment and technologies (Unit: 100 million yen) 3,000 ICT services Biological measurement equipment 2,500 2,000 1,500 1,000 500 0 1,43 385 1,053 1,933 806 1,127 2,637 1,414 1,223 2020 Source: Seed Planning Demand for healthcare is rapidly increasing due to aging of population 7

Synergies from the combination of Minebea and Mitsumi: Core technology in the IoT- advancing sensor technology Expanding business opportunities by advancing sensor technology, a core technology in IoT sensors Atmospheric pressure, temperature and humidity, airflow and object sensing Load sensors / Magnetic sensors Sales volume forecast for each technology in domestic IoT market 2013 ~ 2019 160,000 140,000 120,000 100,000 80,000 60,000 40,000 20,000 0 2013 2014 2015 2016 2017 2018 2019 Intelligent System/Device Platform IoT Infastructure Society Connevity Analytics Service Source: IDC Japan, 2/2015 8

Synergies from the combination of Minebea and Mitsumi: Enhancement of development capabilities and provision of solutions Optical /lighting technologies, Sensors Network technology Minebea's Smart City project in Cambodia Bus and taxi monitoring system Infrastructure monitoring System Parking lot management using surveillance cameras Wi-Fi spot system Waste container monitoring system Building construction monitoring system Smart LED street lights system EV power charging station Traffic Light System Communications technology, Antenna technology Sensors Condition analysis system control boxes Wireless transmission and reception modules Infrastructure radar systems PLC communication modules Lineup of semiconductor products Power supply-related modules 9

Synergies from the combination of Minebea and Mitsumi: Enhancement of development capabilities and provision of solutions Development of ADAS-related products In-car radar, milliwave-related products, in-car cameras Radar module In-car camera Application: Infrastructure Radar Capturing road conditions Application: Milliwave inter-vehicular communication Information sharing between vehicles through milliwave communication Network technologies Joint project with Mitsubishi Heavy Industry and Osaki Electric Surveillance camera monitoring Meter monitoring Distortion sensor monitoring Signal control WiFi spot Street light control Parking sensor monitoring Street light control Application: Network system in towns and infrastructures Communication between vehicles and town 10

Synergies from the combination of Minebea and Mitsumi: Enhancement of development capabilities and provision of solutions Developing Head Up Display (HUD) system PGU(MEMS mirror, Control IC, Driving IC) [Future HUD System] Projection image PGU MEMS mirror [HUD Projection image] High-precision reflection mirror, optical diffusion product, mechanical product Aspherical thin mirror 40.2 bn. yen 2014 actual result 157.3 bn. yen 2020 forecast HUD market forecast Source:Fuji Chimera Research Institute, Inc. 11

Synergies from the combination of Minebea and Mitsumi: SALIOTTM "SALIOTTM"- the first LED lighting equipment capable of automatically adjusting light distribution angle Actuator/Optical element Special optical lens Power supply for LED lighting Wireless Communication PLC Motor driver circuits (100 million yen) World's LED lighting equipment market forecast 50,000 40,000 30,000 20,000 10,000 0 2014-2020 CAGR 19.0% 2012 2013 2015 E 2016 E 2017 E 2018 E 2019 E 2020 E Source :Fuji Keizai 12

Synergies from the combination of Minebea and Mitsumi: Patents in effect (as of Dec. 15, 2015) 1000 800 600 400 200 0 The number of patents in effect held by both companies in Japan and the U.S. reach 2,875 Number of patents in effect Patents in effect 1,525 1,350 2,875 1000 800 600 400 200 0 807 MITSUMI 716 Minebea 718 MITSUMI 634 Minebea 13

Synergies from the combination of Minebea and Mitsumi: Net sales and number of employees Birth of an electro mechanics solutions provider with over 900 billion yen in sales and over 110,000 employees Birth of a company with over 900 billion yen in total sales (Business plan for fiscal year ending March 31, 2018) Employees totaling more than 110,000 (as of September 30, 2015) Sales (bn. yen) 900 bn. yen Number of employees 110,059 1,200 1,000 800 600 400 200 0 750 plus 170 plus 170 750 120,000 100,000 80,000 60,000 40,000 20,000 0 Minebea Passion to Exceed Precision MITSUMI Total 70,206 39,853 39,853 70,206 Minebea Passion to Exceed Precision MITSUMI Total 14

Contacts Minebea may file a registration statement on Form F-4 ("Form F-4") with the U.S. Securities and Exchange Commission (the "SEC") in connection with the possible share exchange (the "Share Exchange") pertaining to a business integration between the two companies, if it is consummated. The Form F-4 (if filed in connection with the Share Exchange) will contain a prospectus and other documents. If a Form F-4 is filed and declared effective, the prospectus contained in the Form F-4 will be mailed to U.S. shareholders of MITSUMI prior to the shareholders' meeting at which the Share Exchange will be voted upon. The Form F-4 and prospectus (if a Form F-4 is filed) will contain important information about the two companies, the Share Exchange and related matters. U.S. shareholders to whom the prospectus is distributed are urged to read the Form F-4, the prospectus and other documents that may be filed with the SEC in connection with the Share Exchange carefully before they make any decision at the shareholders' meeting with respect to the Share Exchange. Any documents filed with the SEC in connection with the Share Exchange will be made available when filed, free of charge, on the SEC's web site at www.sec.gov. In addition, upon request, the documents can be distributed for free of charge. To make a request, please refer to the contact of Minebea below. Minebea Co., Ltd. Corporate Communications Office Phone�F81-3-6758-6703 MITSUMI ELECTRIC CO., LTD. General Affairs Department Phone�F81-42-310-5160 15

Forward-looking statements This document includes "forward-looking statements" that reflect the plans and expectations of Minebea and MITSUMI in relation to, and the benefits resulting from, their business integration described above. To the extent that statements in this document do not relate to historical or current facts, they constitute forward-looking statements. These forward-looking statements are based on the current assumptions and beliefs of the companies in light of the information currently available to them, and involve known and unknown risks, uncertainties and other factors. Such risks, uncertainties and other factors may cause the actual results, performance, achievements or financial position of one or both of the companies (or the group after the integration) to be materially different from any future results, performance, achievements or financial position expressed or implied by these forward-looking statements. The companies undertake no obligation to publicly update any forward-looking statements after the date of this document. Investors are advised to consult any further disclosures by the companies (or the group after the integration) in their subsequent filings in Japan and filings with the U.S. Securities and Exchange Commission. The risks, uncertainties and other factors referred to above include, but are not limited to: (1) economic and business conditions in and outside Japan; (2) changes in demand for PCs and peripherals, information and communication equipment, automobiles, consumer electronics and other devices and equipment, which are the main markets of the companies' products, and in raw material prices, as well as exchange rate fluctuations; (3) changes in interest rates on loans, bonds and other indebtedness of the companies, as well as changes in financial markets; (4) changes in the value of assets (including pension assets) such as securities and investment securities; (5) changes in laws and regulations (including environmental regulations) relating to the companies' business activities; (6) increases in tariffs, imposition of import controls and other developments in the companies' main overseas markets; (7) interruptions in or restrictions on business activities due to natural disasters, accidents and other causes; (8) the companies' being unable to reach an agreement satisfactory to both of them with respect to the details of the business integration or otherwise being unable to complete the business integration; (9) difficulty of realizing synergies or added value from the business integration by the group after the integration. 16