If we need to modify the design after confirming the sample, what is the process and additional cost

First, please provide detailed modification requirements (e.g., size adjustment, material replacement). Our R&D team will evaluate the impact of the modification on the production process and cost within 1-2 working days. If the modification is minor (e.g., small size tweaks), there is usually no additional cost, and the sample lead time will be extended by 2-3 working days. For major modifications (e.g., structural redesign), a small modification fee and extended sample time (3-5 working days) will apply, and we will confirm the details with you in writing before proceeding.