Quality Policy

Document No.: POL-01 · Revision: 00 · Effective: October 2026 · Approved by: General Manager

At STU Treyler, our guiding principle in the design, manufacture and after-sales support of semi-trailers and trailers is to deliver safe, durable products that meet our customers’ expectations and fully comply with legal and type-approval requirements.

To this end, top management is committed to the following:

1. Customer focus: Understanding our customers’ needs, fulfilling every contractual and order requirement, and evaluating feedback systematically to increase customer satisfaction continually.
2. Regulatory and type-approval compliance: Manufacturing our products in conformity with the types approved under Regulation (EU) 2018/858, the relevant UN Regulations and national legislation; safeguarding conformity of production (CoP) and ensuring that every vehicle meets the values declared in its Certificate of Conformity (CoC).
3. Safety first: Never compromising on safety-critical systems such as braking, lighting, coupling and load securing, and treating safety as the first priority in design, manufacture and inspection.
4. Management of software and electronic systems: Managing the configuration and updating of software-based systems on our vehicles (e.g. EBS brake control units) through our Software Update Management System (SUMS) under UN Regulation No. 156, as an integral part of our quality management system.
5. Traceability: Making every vehicle traceable by its vehicle identification number (VIN) through records of materials, welding, painting, assembly, testing and software/parameter settings, and retaining these records for the required period.
6. Supplier management: Selecting, evaluating and developing our suppliers against quality, delivery and regulatory-compliance criteria, and using only approved and certified parts for critical components.
7. Risk-based thinking: Identifying risks and opportunities in our processes, preventing defects at source through preventive action, and analysing the root causes of nonconformities to implement lasting corrective action.
8. Competent and committed people: Investing in the training and competence of our employees, promoting quality awareness at every level, protecting occupational health and safety, and encouraging everyone to take part in improvement.
9. Continual improvement: Setting measurable quality objectives, monitoring our performance regularly, and continually improving the effectiveness of our quality management system through internal audits and management reviews.
10. Respect for the environment and society: Conducting our activities in an environmentally responsible manner, using resources efficiently and managing waste in accordance with the law.

This policy has been approved by top management. It is communicated to all employees, made available to interested parties on our website and reviewed for continuing suitability at least once a year in the management review.

STU Treyler Dorse İthalat İhracat Ltd. Şti. — General Manager