1. According to the inquiry of R&D Investment Brand House, Baodao Optics has invested a lot of resources in R&D to explore new materials and technologies to improve the quality and performance of its products.

2. Material selection: Bao Dao glasses are very demanding in material selection, and high-quality materials are selected to ensure product quality.

3. Manufacturing technology: Each pair of Bao Dao glasses is hand-made by highly trained craftsmen. These craftsmen need long-term training and work experience to master this exquisite craftsmanship.