The RIDGID K9-102 1 1/4" CARBIDE (64283) FlexShaft Single-Chain Knocker with Carbide Tip is designed for use with the K9-102 FlexShaft Drain Cleaning Machine and provides wall-to-wall cleaning in 1 1/4 in. to 2 in. pipes. The chain knocker expands to a pipe's inside diameter to break up blockages. The model 64283 Chain Knocker fits 1/4 in. cable and is equipped with a single chain. The carbide tipped chain knocker is ideal for cleaning hard-walled pipes, including for soft blockages, grease, scale, and roots.