Hello, if you put forward new ideas or improvements on the manufacturing method, product technology or product itself of the frame/shell, you can apply for an invention patent;
If the shape and structure of the frame/shell are improved and suitable for practical use, you can apply for a patent for utility model;
If only the shape, pattern and color of the frame/shell are newly designed, you can apply for a design patent.
Compared with invention patents, the level of creativity of utility model patents is low. Invention patents and utility model patents are technical solutions, involving products or manufacturing methods; Design pays more attention to the decoration or artistry of products.