The material is a modified medical material typically developed by our R&D team. Compared with traditional PETG, the innovative material manifests superior performance in several aspects such as elongation at break, tensile strength, ductility, chemical resistance, abrasion resistance, stress retention ratio, etc. Besides, our material can be designed to be thinner, more stretchable, and more resistant to high temperatures than materials of other retainers/invisible appliances. In addition, due to more specific requirements of bio-mechanical performance for aligners, our team developed composite layer sheets with different orthodontic forces, which has considered the movement of easiness of teeth for various densities of alveolar bone by providing comprehensive orthodontic solution from early to the final stage.