Renssi Chain Knockers
Depending on the size of the tool, it has one to three chains with solid carbide inserts brazed on the chainlinks. Because of the inserts, the pipe is cleaned out of rust and dirt very effectively.
There are two different types of connections to the rotating wire. The wire can be put through the tool and tightened using allen screws or it can be connected using T-slide connectors.
US PATENT
Renssi® Chain Knockers are specific tools. They have received US Patent No. 9,649,671 B2