This device is a manual spiral punching and binding machine, used for assembling and organizing documents, research papers, and A4-sized booklets. Key uses and functions of the machine: Punching Papers: Punching a stack of papers at once (usually ranging from 10 to 12 sheets depending on paper thickness) with a 21-hole format. Plastic Comb Binding: Opening the plastic spiral comb to insert the punched papers and then closing it to assemble the book. High Binding Capacity: Supports binding of large files with a capacity of approximately 450 sheets when using the appropriate comb size.