A hole expander can enlarge holes on plastic boards, usually used for punching holes on wooden boards and plastic boards, and cannot be used on metal Plate drilling. First, drill a small hole on the plastic board with a drill, and then repeatedly rotate the reamer to create a tapered hole. The reamer has two grooves on top for removing debris. This reamer is made of alloy steel, which is sturdy and durable. It is very convenient to use and can be used when not in use Put on a metal pen cap for safety assurance. Expandable aperture: 0-14mm [Product Material]: High hardness alloy+engineering plastic Product weight: approximately 53.11g [Pen body length]: 12.7cm [Total length after covering with metal cap]: 13.5cm