Thank you for viewing. DC Jack Plug Conversion Adapter Outer Diameter 5.5mm / Inner Diameter 2.1mm ⇒ Outer Diameter 4.0mm / Inner Diameter 1.7mm Center Pinless For laptops, mobile power supplies, chargers, routers, etc. ■ This product can be directly inserted into a 5.5mm (outer diameter) x 2.1mm (inner diameter) standard power interface for conversion. All interfaces are completed with a single power cable interface. ■ Outer Diameter 5.5mm / Inner Diameter 2.1mm ⇒ Outer Diameter 4.0mm / Inner Diameter 1.7mm Center Pinless ■ Can be used for converting various chargers such as laptops, PCs, razors, routers, and broadband equipment. ■ Please be sure to check the size before ordering to ensure it is correct. ※ Please note that this is a bulk product, so there is no packaging or instruction manual.