Product parameters: The flexible shaft and accessories are suitable for cleaning diameter: 6.4-25.4mm (1/4-1 inch, detailed size: M4 thread: 6.5, 7.9, 9.1; M6 connector: 11.1, 12.7, 14.3, 15.9, 17.5, 19.1, 20.6, 22.1, 23.8, 25.4)