DC Jack Connector Size: 5.5MM x 2.1MM (External Diameter x Internal Diameter ); This dc power plug is made of high quality PVC flame retardant plastic with good electrical conductivity and corrosion resistance; Easy to handle, just insert the cables in the holes, twist and lock in place, and only then solder; Perfect for making a cable to a desired length or replacing a broken connector.; Suitable for small electronic projects and CCTV applications