There are many styles of envelopes, including Chinese envelopes, Western envelopes, diamond envelopes, file bags, and window envelopes, etc. Each style has its unique design and function to meet different usage needs. For example, Chinese envelopes typically have an opening on the short side, making it convenient for writing and sealing. Specifications: Size 5 (DL) 220×110mm and C4 type 324×229mm.
