Feng Hsin-KY: Announcement of Endorsement Guarantee in accordance with Article 25, Paragraph 1, Subparagraphs 2, 3, and 4 of the Regulations Governing Loans and Endorsements/Guarantees by Public Companies

1. Date of occurrence of the event: 2026/05/05 2. Company receiving endorsement/guarantee: (1) Company name: Vietnam Precision Industrial No.1 Co., Ltd. (2) Relationship with the company providing endorsement/guarantee: A 100% indirectly owned subsidiary of our company (3) Limit of endorsement/guarantee (NT$ thousands): 2,440,794 (4) Original balance of endorsement/guarantee (NT$ thousands): 255,840 (5) Amount of new endorsement/guarantee (NT$ thousands): 479,700 (6) Balance of endorsement/guarantee as of the date of occurrence (NT$ thousands): 735,540 (7) Actual amount drawn by the company receiving endorsement/guarantee (NT$ thousands): 0 (8) Reason for new endorsement/guarantee: The subsidiary needs a bank credit line, and the parent company provides endorsement/guarantee. 3. Collateral provided by the company receiving endorsement/guarantee: (1) Content: None (2) Value (NT$ thousands): 0 4. Latest financial statements of the company receiving endorsement/guarantee: (1) Capital (NT$ thousands): 766,555 (2) Accumulated earnings/losses (NT$ thousands): 6,035,754 5. Conditions for release of endorsement/guarantee liability: (1) Conditions: When the subsidiary repays the bank loan (2) Date: Bank contract maturity date 6. Total limit of endorsement/guarantee (NT$ thousands): 3,050,993 7. Balance of endorsement/guarantee as of the date of occurrence (NT$ thousands): 988,480 8. As of the date of occurrence, the ratio of endorsement/guarantee balance to the net worth of the public company's latest financial statements: 0.16 9. As of the date of occurrence, the combined ratio of endorsement/guarantee, long-term investment, and loans to the net worth of the public company's latest financial statements: 0.34 10. Other matters to be specified: None