According to the proposed materials, process and size specifications, draw engineering drawings for customer products to ensure that the physical effect of products has “zero” deviation and meets the display effect desired by customers. At the same time, Dahua also accepts direct contributions from customers. According to the proposed materials, process and size specifications, draw engineering drawings for customer products to ensure that the physical effect of products has “zero” deviation and meets the display effect desired by customers. At the same time, Dahua also accepts direct contributions from customers. According to the proposed materials, process and size specifications, draw engineering drawings for customer products to ensure that the physical effect of products has “zero” deviation and meets the display effect desired by customers. At the same time, Dahua also accepts direct contributions from customers.