RIDGID offers a wide variety of Flex Shaft accessories in different sizes for the most cleaning efficiency on the jobsite. Depending on pipe size, pipe material and blockage, there are different chain Knockers and Brushes for every job. Knowing when to choose Brushes or standard, carbide tipped or penetrating head chain Knockers can help you get the best performance out of your machine. This bundle includes the carbide tipped, double chain knocker plus a penetrating head (catalog number 66573), the penetrating ball head accessory (catalog number 71838), and the smooth, double-chain knocker (catalog number 64298) for use with the RIDGID Flex Shaft K9-12, K9-102+, K9-204+ drain cleaning machine and attaches to the end of the 1/4 in. cable (not included). These attachments are designed to clear grease, scale, light roots, wipes and other soft blockages found in 2 in. pipes.